Intelligent electronic switch, integrated circuit chip, chip product and electromechanical device

Abstract

The invention provides an intelligent electronic switch for processing an open circuit of a current limiting end. The intelligent electronic switch comprises the current limiting end and a switch control unit, a power switch; the current limiting generation module is connected with the current limiting end, the current limiting generation module generates a corresponding first current limiting signal based on the resistance value of the adjusting resistor, and when the current limiting end is in an open circuit, the current limiting generation module stops generating the first current limiting signal; the open circuit processing module is connected with the current limiting end, and when the open circuit processing module detects that the current limiting end is in an open circuit, the open circuit processing module outputs a preset second current threshold value; the current limiting control unit is connected with the open circuit processing module, when the current flowing through the power switch is larger than or equal to a third current limiting threshold value, the current limiting control unit limits the current flowing through the power switch, and the third current limiting threshold value corresponds to the first current limiting signal or the second current threshold value. The invention also provides an integrated circuit chip, a chip product and electromechanical equipment.

Description

Technical Field

[0001] The present application relates to the field of intelligent semiconductor switches, and in particular to an intelligent electronic switch, an integrated circuit chip, a chip product and an electromechanical device. Background Art

[0002] Smart electronic switches are usually used to couple loads with power supplies and are electronic components that control the on and off of load circuits. Smart electronic switches also have one or more diagnostic capabilities and protection features, such as protection against over-temperature, overload, over-current, and short-circuit events. For example, a power switch is provided in a smart electronic switch, and in situations such as over-temperature events, the power switch is disconnected, disconnecting the path between the power supply and the load. Smart electronic switches are widely used in automotive electronics, industrial automation, medical equipment, and other fields.

[0003] The related art proposes an intelligent electronic switch, one of whose protection characteristics is current limiting, that is, when an overcurrent or short circuit event occurs, it limits the current flowing through the power switch, so that the current flowing through the power switch will not increase to a large extent, which is beneficial to protecting the power switch. In order to improve the application scope of the intelligent electronic switch, the related art proposes that the intelligent electronic switch has a current limiting end, and the current limiting end is used to connect an external adjustment resistor. According to the current limiting end, the adjustment resistors with different resistance values ​​are connected to achieve different current limiting thresholds.

[0004] In order to obtain the current limiting value, the specification of the intelligent electronic switch requires that the current limiting end must be connected to an external regulating resistor. However, during actual manufacturing at the factory, there is a certain probability that the regulating resistor will be omitted from being connected to the current limiting end. This will cause the power switch to fail to stably conduct when connected to the load, and the power switch will remain disconnected, causing problems in the normal use of the intelligent electronic switch. Summary of the invention

[0005] The technical problem to be solved by the embodiments of the present application is to provide an intelligent electronic switch, an integrated circuit chip, a chip product and an electromechanical device to address the deficiencies of the prior art. The open circuit of the current limiting end of the intelligent electronic switch can be processed.

[0006] In order to solve the above technical problems, a first aspect of an embodiment of the present application provides an intelligent electronic switch for processing an open circuit of a current limiting end, comprising:

[0007] A power supply terminal, a power ground terminal, a load output terminal, a current limiting terminal, and a switch control unit, wherein the power supply terminal is used to connect to the positive electrode of the power supply, the power ground terminal is used to connect to the negative electrode of the power supply, the load output terminal is used to connect to the load, and the current limiting terminal is used to connect to the regulating resistor;

[0008] A power switch, a first end of which is connected to a power supply end or a power ground end, a second end of which is connected to a load output end, and a control end of which is connected to a switch control unit, the switch control unit being used to control the power switch to be turned on or off;

[0009] a current limiting generating module connected to the current limiting end, wherein the current limiting generating module generates a corresponding first current limiting signal based on the resistance value of the regulating resistor, and when the current limiting end is open, the current limiting generating module stops generating the first current limiting signal;

[0010] an open circuit processing module, which is connected to the current limiting end, and outputs a preset second current threshold when the open circuit processing module detects that the current limiting end is open circuit;

[0011] A current limiting control unit is connected to the open circuit processing module, and when the current flowing through the power switch is greater than or equal to a third current limiting threshold, the current limiting control unit limits the current flowing through the power switch, and the third current limiting threshold corresponds to the first current limiting signal or the second current threshold.

[0012] Optionally, when the open circuit processing module detects that the current limiting end is open circuited, it controls the current limiting generation module to stop limiting the current of the power switch;

[0013] The open circuit processing module includes an open circuit detection module and a current switching module;

[0014] The open circuit detection module is connected to the current limiting end and the current switching module. The open circuit detection module determines whether the current limiting end is open based on the voltage of the current limiting end. When the open circuit detection module determines that the current limiting end is in an open circuit state, it outputs a first open circuit signal to the current switching module, and the current switching module receives the first open circuit signal and controls the output of the second current threshold to the current limiting control unit; when the open circuit detection module determines that the current limiting end is in a non-open circuit state, it outputs a second open circuit signal to the current switching module, and the current switching module receives the second open circuit signal and controls the output of a signal derived from the first current limiting signal to the current limiting control unit.

[0015] Optionally, the open circuit processing module includes a short circuit processing module, the short circuit processing module includes a short circuit current generating unit and a second comparison and selection unit, the second comparison and selection unit is connected to the short circuit current generating unit and the current limiting generating module, the short circuit current generating unit is used to generate a first short circuit current signal, and the second comparison and selection unit converts the first short circuit current signal into a first current threshold;

[0016] Among them, when the current switching module receives the first open-circuit signal, it controls the output of the second current threshold to the current limiting control unit; when the current switching module receives the second open-circuit signal, it controls the output of the first current threshold or a signal derived from the first current limiting signal to the current limiting control unit, and the first current threshold and the second current threshold are the same signal.

[0017] Optionally, the second comparison and selection unit includes a third-first current mirror and a third-second current mirror, wherein the third-first current mirror is connected to the current limiting generation module, and the third-second current mirror is connected to the short-circuit current generation unit;

[0018] The third-first current mirror is used to mirror the current flowing through the current limiting generation module to obtain a first current corresponding signal, the third-second current mirror mirrors the first short-circuit current signal to obtain a first current threshold, the third-first current mirror includes a tenth MOS transistor, the third-second current mirror includes an eleventh MOS transistor, the tenth MOS transistor is connected in series with the eleventh MOS transistor, the tenth MOS transistor is used to output the first current corresponding signal, the eleventh MOS transistor is used to output the first current threshold, the tenth MOS transistor and the eleventh MOS transistor work together to output the smaller of the first current corresponding signal and the first current threshold, wherein the first current corresponding signal corresponds to the first current limiting signal;

[0019] When the current switching module receives the first open-circuit signal, the current switching module controls the first current limiting signal to stop being output to the third current mirror or short-circuits the source and drain of the tenth MOS tube.

[0020] Optionally, the current limiting generation module includes a first current mirror, and the first current mirror converts the first current limiting signal into a first intermediate signal and outputs it to a third current mirror;

[0021] The first current mirror includes a thirteenth MOS tube and a fourteenth MOS tube, wherein a first end of the thirteenth MOS tube is connected to the first internal power supply, a control end of the thirteenth MOS tube is connected to a second end thereof, and the second end of the thirteenth MOS tube is used to access a first current limiting signal; a first end of the fourteenth MOS tube is connected to the first internal power supply, a control end of the fourteenth MOS tube is connected to a control end of the thirteenth MOS tube, and a second end of the fourteenth MOS tube is used to output a first intermediate signal;

[0022] The third-first current mirror includes a ninth MOS tube and a tenth MOS tube, wherein the first end of the ninth MOS tube is connected to the second end of the fourteenth MOS tube to receive the first intermediate signal, the control end of the ninth MOS tube is connected to the first end thereof, the second end of the ninth MOS tube is connected to the third-second current mirror, the second end of the tenth MOS tube is connected to the third-second current mirror, the control end of the tenth MOS tube is connected to the control end of the ninth MOS tube, and the first end of the tenth MOS tube is used to output the first current corresponding signal, and the first current corresponding signal corresponds to the first intermediate signal;

[0023] The third second current mirror includes a seventh MOS tube, an eighth MOS tube and an eleventh MOS tube, wherein the first end of the seventh MOS tube is connected to the short-circuit current generating unit to access the first short-circuit current signal, the control end of the seventh MOS tube is connected to the first end thereof, and the second end of the seventh MOS tube is connected to the power ground terminal; the first end of the eighth MOS tube is connected to the second end of the ninth MOS tube, the control end of the eighth MOS tube is connected to the control end of the seventh MOS tube, and the second end of the eighth MOS tube is connected to the power ground terminal; the first end of the eleventh MOS tube is connected to the second end of the tenth MOS tube, the control end of the eleventh MOS tube is connected to the control end of the seventh MOS tube, and the second end of the eleventh MOS tube is connected to the power ground terminal;

[0024] The current switching module includes a seventeenth switch tube, two ends of the seventeenth switch tube are correspondingly connected to two ends of the tenth MOS tube, and the control end of the seventeenth switch tube is used to receive the first open circuit signal or the second open circuit signal. When the seventeenth switch tube receives the first open circuit signal, the seventeenth switch tube is turned on to short-circuit the tenth MOS tube or the fourteenth MOS tube; or,

[0025] The current switching module includes a seventeenth switch tube and a current source, the seventeenth switch tube is connected in series with the current source, the two ends of the series branch are correspondingly connected to the two ends of the fourteenth MOS tube, the control end of the seventeenth switch tube is used to receive the first open circuit signal or the second open circuit signal, and when the seventeenth switch tube receives the first open circuit signal, the seventeenth switch tube is turned on.

[0026] Optionally, when the open circuit detection module determines that the current limiting end changes from an open circuit state to a non-open circuit state, the open circuit detection module delays outputting a second open circuit signal to the current switching module.

[0027] Optionally, the open circuit detection module includes a capacitor and a second current limiting element, wherein when the open circuit detection module determines that the current limiting end is changed from an open circuit state to a non-open circuit state, the capacitor is discharged through the second current limiting element, and when the voltage on the capacitor is discharged to be less than a preset threshold voltage, the open circuit detection module outputs a second open circuit signal to the current switching module.

[0028] Optionally, the open circuit processing module includes an open circuit detection module and a current switching module, the open circuit detection module is used to determine whether the current limiting end is open circuit, and the open circuit detection module is connected to the current switching module;

[0029] The current switching module comprises a threshold current branch, a first end of the threshold current branch is connected to the current limiting end, a second end of the threshold current branch is connected to the power ground end, and the threshold current branch comprises a fifth switch and a fifth resistor connected in series;

[0030] When the open circuit detection module detects that the current limiting terminal is open circuit, it outputs a first open circuit signal to the current switching module, and the current switching module controls the fifth switch to be locked and turned on to generate the second current threshold through the current limiting generation module.

[0031] Optionally, the current switching module includes a logic processing unit and a third comparator, the logic processing unit is connected to the open circuit detection module and the output end of the third comparator, the first input end of the third comparator is connected to the signal derived from the second current threshold, and the second input end of the third comparator is connected to a reference signal, and the reference signal is greater than the signal derived from the second current threshold;

[0032] When the signal at the first input terminal of the third comparator is greater than the signal at the second input terminal thereof, the logic processing unit controls the fifth switch to be turned off.

[0033] Optionally, the open circuit processing module includes a pull-up branch, one end of which is connected to the first internal power supply, and the other end of which is connected to the current limiting end. When the current limiting end is in an open circuit state, the pull-up branch pulls up the voltage of the current limiting end to the voltage of the first internal power supply.

[0034] Optionally, the maximum output current of the pull-up branch is less than half of the minimum first current limiting signal allowed to flow through the current limiting end, wherein the minimum first current limiting signal allowed to flow through the current limiting end corresponds to the first current limiting signal when the maximum adjustment resistance allowed to be connected to the current limiting end.

[0035] Optionally, when the current flowing through the power switch is greater than or equal to a third current limiting threshold, the current limiting control unit controls the current flowing through the power switch to be equal to the third current limiting threshold; or,

[0036] The current limiting generating module includes an operational amplifier and a twelfth MOS tube, wherein a first input terminal of the operational amplifier is connected to a first reference voltage, a second input terminal of the operational amplifier is connected to the current limiting terminal, an output terminal of the operational amplifier is connected to a control terminal of the twelfth MOS tube, a first terminal of the twelfth MOS tube is used to output a first current limiting signal, a second terminal of the twelfth MOS tube is connected to the current limiting terminal, wherein the first current limiting signal is less than a ratio of the first reference voltage to the regulating resistor.

[0037] A second aspect of an embodiment of the present application provides an integrated circuit chip, comprising the above-mentioned intelligent electronic switch, wherein the power supply end is a power supply pin, the power ground end is a power ground pin, the load output end is a load output pin, and the current limiting end is a current limiting pin.

[0038] A third aspect of the embodiments of the present application provides a chip product, comprising the above-mentioned intelligent electronic switch, wherein the components of the intelligent electronic switch except the power switch are located on a first integrated circuit chip, and the power switch is located on a second integrated circuit chip;

[0039] Among them, the power supply end is a power supply pin, the power ground end is a power ground pin, the load output end is a load output pin, the current limiting end is a current limiting pin, the power supply pin, the power ground pin, and the current limiting pin are located on a first integrated circuit chip, and the load output pin is located on a second integrated circuit chip.

[0040] A fourth aspect of the embodiments of the present application provides an electromechanical device, including the above-mentioned intelligent electronic switch or the above-mentioned integrated circuit chip or the above-mentioned chip product;

[0041] It also includes a power supply, an adjusting resistor, a load and a microprocessor, wherein the positive pole of the power supply is connected to the power supply terminal, the negative pole of the power supply is connected to the power ground terminal, one end of the load is connected to the load output terminal, the other end of the load is connected to the power ground terminal or the power supply terminal, the microprocessor is connected to the intelligent electronic switch, the first end of the adjusting resistor is connected to the current limiting terminal, and the second end of the adjusting resistor is connected to the power ground terminal.

[0042] Optionally, the electromechanical device includes a car.

[0043] In this embodiment, an open circuit processing module is added, and the open circuit processing module is connected with the current limiting end, the current limiting generation module, and the current limiting control unit. When the open circuit processing module detects that the current limiting end is open, it outputs a preset second current threshold value, and controls the current limiting generation module to stop limiting the current of the power switch. The current limiting control unit is connected with the open circuit processing module. When the current flowing through the power switch is greater than or equal to the third current limiting threshold value, the current limiting control unit limits the current flowing through the power switch, and the third current limiting threshold value corresponds to the first current limiting signal or the second current threshold value. Therefore, when the current limiting end is in an open circuit state due to unintentional, the open circuit processing module of the intelligent electronic switch can detect this state and output the preset second current threshold value to the current limiting control unit. At this time, the first current limiting signal does not work. The current limiting control unit determines whether the current flowing through the power switch is overcurrent based on the second current threshold value, so that even if the power switch is loaded, it can be normally opened as needed. The open circuit of the current limiting end will not affect the normal use of the intelligent electronic switch, and will not cause inconvenience to the normal use of the intelligent electronic switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1a is a circuit module diagram of the electromechanical device of the first embodiment of the present application;

[0046] Figure 1b is a circuit module diagram of an electromechanical device according to another embodiment of the present application;

[0047] Figure 2 It is a circuit module diagram of the first embodiment of the present application in which the intelligent electronic switch is connected to the regulating resistor;

[0048] Figure 3a is a detailed circuit module diagram of the intelligent electronic switch of the first embodiment of the present application;

[0049] Figure 3b is a detailed circuit module diagram of an intelligent electronic switch according to another embodiment of the present application;

[0050] Figure 4 It is a circuit module diagram of the second embodiment of the present application in which the intelligent electronic switch is connected to the regulating resistor;

[0051] Figure 5 is a detailed circuit module diagram of the intelligent electronic switch of the second embodiment of the present application;

[0052] Figure 6 It is a circuit module diagram of the third embodiment of the present application in which the intelligent electronic switch is connected to the regulating resistor;

[0053] Figure 7a is a detailed circuit module diagram of the intelligent electronic switch of the third embodiment of the present application;

[0054] Figure 7b is a detailed circuit module diagram of an intelligent electronic switch according to another embodiment of the present application;

[0055] Figure 8 is a detailed circuit module diagram of the intelligent electronic switch of the fourth embodiment of the present application;

[0056] Fig. 9 is a circuit module diagram of a fifth embodiment of the present application in which an intelligent electronic switch is connected to an adjustable resistor;

[0057] Fig.10 It is a detailed circuit module diagram of the intelligent electronic switch of the fifth embodiment of the present application. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0059] The terms "including" and "having" and any variations thereof appearing in the specification, claims and drawings of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or modules is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units that are inherent to these processes, methods, products or devices. In addition, the terms "first", "second" and "third" are used to distinguish different objects, rather than to describe a specific order. The connection of this application includes direct connection and indirect connection. Indirect connection means that other electronic components, pins, etc. may exist between the two connected components. The XX pin mentioned in this application may be an actual pin, or it may not be an actual pin, for example, it is only a pin of a component or a pin of a wire. The three situations mentioned and / or included in this application, such as A and / or B, include the three situations of A, B, A and B.

[0060] First embodiment

[0061] The present application embodiment provides an electromechanical device, such as an automobile, medical equipment, industrial automation equipment, aerospace equipment, etc. Figure 1a The electromechanical device includes a power supply 110, a load 120, a microprocessor 300 and an intelligent electronic switch 200. The power supply 110 is generally a battery, which is generally a storage battery. The storage battery provides voltages such as 12V, 24V, 36V, 48V, 60V, etc., and it can also be other types of batteries or power supplies. The load 120 includes at least one of a resistive load 120, an inductive load 120 and a capacitive load 120. The resistive load 120 is, for example, a seat adjustment device, an auxiliary heating device, a window heating device, a light emitting diode (LED), a rear lighting or other resistive loads 120. The inductive load 120 is, for example, a pump, an actuator, a motor, an anti-lock braking system (ABS), an electronic braking system (EBS), a fan or other systems including an inductive load 120 for one or more wiper systems. The capacitive load 120 is, for example, a lighting element, such as a xenon arc lamp. In the figure, the load 120 is only indicated by one element, and the load 120 is usually a more complex load, such as a module or subsystem with a large number of components. The microprocessor 300 is connected to the intelligent electronic switch 200 to control the intelligent electronic switch 200. At the same time, the intelligent electronic switch 200 feeds back its state and related parameter information, such as related parameter information of diagnosis, current parameter information, voltage parameter information, etc., to the microprocessor 300 for processing.

[0062] In this embodiment, the intelligent electronic switch 200 includes a power supply terminal VCC, a power ground terminal GND, and a load output terminal OUT, wherein the power supply terminal VCC is connected to the positive electrode of the power supply 110, the power ground terminal GND is connected to the negative electrode of the power supply 110, the load output terminal OUT is connected to one end of the load 120, and the other end of the load 120 is connected to the negative electrode or the positive electrode of the power supply 110. In addition, in other embodiments of the present application, an anti-reverse connection diode and a current limiting resistor may be further provided between the power ground terminal GND and the negative electrode of the power supply 110.

[0063] In this embodiment, the intelligent electronic switch 200 further includes a power switch M1 and a switch control unit 220. One end of the power switch M1 is connected in series with the load 120 via the load output terminal OUT, and the other end is connected to the power supply terminal VCC or the power ground terminal GND. The control end is connected to the switch control unit 220, and the switch control unit 220 is used to control whether the power switch M1 is turned on. In this embodiment, the power switch M1 is an enhanced NMOS tube, an enhanced PMOS tube, a junction FET or an IGBT, etc. The enhanced NMOS tube is used as an example for illustration in the figure. The power switch M1 can be implemented as a silicon device, or can be implemented using other semiconductor materials, such as silicon carbide (SiC), gallium arsenide (GaAs) or gallium nitride (GaN).

[0064] exist Figure 1a In the embodiment, the power switch M1 is connected as a high-side switch, which is a switch connected between the power supply terminal VCC and the load 120. However, the present application is not limited thereto. In other embodiments of the present application, see Figure 1b , the power switch M1 is connected as a low-side switch, which is a switch connected between the load 120 and the power ground GND.

[0065] Please refer to Figure 1a , Figure 2 and Figure 3a In this embodiment, the intelligent electronic switch 200 includes a current limiting terminal CL and a current limiting generating module 230. The current limiting terminal CL is used to connect the first end of the regulating resistor R0, and the second end of the regulating resistor R0 is connected to the power ground terminal GND. The resistance range of the regulating resistor R0 is generally specified in the product specification of the intelligent electronic switch 200. For example, the resistance range of the regulating resistor R0 is 5kΩ-100kΩ, for example, specifically 5kΩ, 10kΩ, 50kΩ, 100kΩ, etc. This application does not impose specific restrictions on the resistance of the regulating resistor R0, and technicians in this field can set it as needed. In this embodiment, the current limiting generating module 230 is connected to the current limiting terminal CL, and the current limiting generating module 230 generates a first current limiting signal based on the resistance of the regulating resistor R0. The first current limiting signal corresponds to the resistance of the regulating resistor R0. In this embodiment, the first current limiting signal is a current.

[0066] In the present embodiment, the current limiting generating module 230 includes an operational amplifier OP1 and a twelfth MOS tube M12, wherein the non-inverting input terminal of the operational amplifier OP1 is connected to a first reference voltage, and the first reference voltage is, for example, 0.5V, 0.6V, 0.7V, 0.8V, 0.9V, 1V, etc., the reverse input terminal of the operational amplifier OP1 is connected to the current limiting terminal CL, the output terminal of the operational amplifier OP1 is connected to the control terminal of the twelfth MOS tube M12, the second terminal of the twelfth MOS tube M12 is connected to the current limiting terminal CL, and the first terminal of the twelfth MOS tube M12 is used to output a first current limiting signal. In the present embodiment, the twelfth MOS tube M12 is an enhanced NMOS tube. In the present embodiment, when the current limiting terminal CL is connected to the regulating resistor R0, the voltage at the reverse input terminal of the operational amplifier OP1 is equal to the voltage at the non-inverting input terminal, which is the first reference voltage, and the current flowing through the regulating resistor R0 is:

[0067] Vref1 / R0;

[0068] Wherein, Vref1 is the voltage value of the first reference voltage, and R0 is the resistance value of the regulating resistor R0. In this embodiment, there is a certain difference between the first current limiting signal and the current flowing through the regulating resistor R0 (please refer to the following description). However, the present application is not limited to this. In other embodiments of the present application, the first current limiting signal can also be the same as the current flowing through the regulating resistor R0.

[0069] In this embodiment, the intelligent electronic switch 200 includes a current limiting control unit 250. Under normal circumstances, when the current flowing through the power switch M1 is greater than or equal to the third current limiting threshold, the current limiting control unit 250 limits the current flowing through the power switch M1. When the current limiting terminal CL is normally connected to the regulating resistor R0, the third current limiting threshold corresponds to the first current limiting signal. When the current limiting terminal CL is open, the third current limiting threshold corresponds to a preset second current threshold (see the following description).

[0070] In this embodiment, one implementation of the current limiting control unit 250 is shown in Figure 3aThe current limiting control unit 250 includes a current detection unit 251, a first comparator A1 and a third MOS tube M3. The current detection unit 251 is used to output a detection current signal, which is used to characterize the current flowing through the power switch M1. The first input end of the first comparator A1 is connected to the detection current signal, and the second input end of the first comparator A1 is used to connect to the second reference threshold, which is proportional to the first current limiting signal or the second current threshold. The output end of the first comparator A1 is connected to the control end of the third MOS tube M3, the first end of the third MOS tube M3 is connected to the control end of the power switch M1, and the second end of the third MOS tube M3 is connected to the load output end OUT. In this embodiment, when the detection current signal is greater than or equal to the second reference threshold, it means that the current flowing through the power switch M1 is greater than or equal to the third current limiting threshold, and the first comparator A1 outputs a control signal to the third MOS tube M3, and the third MOS tube M3 adjusts the voltage of the control end of the power switch M1 to achieve that the detection current signal is equal to the second reference threshold, that is, the current flowing through the power switch M1 is equal to the third current limiting threshold through adjustment, and the third current limiting threshold corresponds to the second reference threshold. In this embodiment, the first comparator A1 is a voltage comparator, and the detection current signal and the second reference threshold are voltages. Of course, those skilled in the art can also adjust them as needed. In this embodiment, the third MOS tube M3 is an enhanced NMOS tube. In addition, in other embodiments of the present application, when the detection current signal is greater than or equal to the second reference threshold, the current limiting control unit 250 can control the current flowing through the power switch M1 to be a preset current as needed, and the preset current may not be equal to the third current limiting threshold.

[0071] In this embodiment, the current detection unit 251 includes a second MOS tube M2 and a first resistor R1, wherein the second MOS tube M2 is a mirror tube of the power switch M1, the type of the second MOS tube M2 is the same as the type of the power switch M1, the current flowing through the second MOS tube M2 is substantially proportional to the current flowing through the power switch M1, for example, the ratio of the current flowing through the power switch M1 to the current flowing through the second MOS tube M2 is 100:1, 1000:1, 5000:1, 10000:1, etc., the control end of the second MOS tube M2 is connected to the control end of the power switch M1, the first end of the second MOS tube M2 is connected to the first end of the power switch M1, the second end of the second MOS tube M2 is connected to the first end of the first resistor R1, the second end of the first resistor R1 is connected to the load output end OUT, the second end of the second MOS tube M2 is connected to the first input end of the first comparator A1, and the signal at the second end of the second MOS tube M2 is the detection current signal, that is, the voltage of the first end of the first resistor. In addition, in other embodiments of the present application, the current detection unit 251 may not be limited to the above-mentioned circuit. For example, the current detection unit 251 includes a first resistor R1, and the first resistor R1 is connected in series with the power switch M1. For example, the first end of the first resistor R1 is connected to the second end of the power switch M1, and the second end of the first resistor R1 is connected to the load output end OUT. At this time, the voltage at the first end of the first resistor R1 is the detection current signal.

[0072] In this embodiment, the current limiting control unit 250 includes a second current mirror and a second resistor R2, the second current mirror is used to convert the signal or the second current threshold from the first current limiting signal into a second intermediate signal, and the second intermediate signal is used to output to the second resistor R2 to obtain a second reference threshold. Specifically, in this embodiment, the second current mirror includes a second-first current mirror, and the second-first current mirror includes a fifteenth MOS tube M15 and a sixteenth MOS tube M16, wherein the first end of the fifteenth MOS tube M15 is connected to the second internal power supply 221, the control end of the fifteenth MOS tube M15 is connected to its second end, and the second end of the fifteenth MOS tube M15 is used to directly or indirectly access the first current limiting signal or the second current threshold, and when the current limiting end CL is normally connected to the regulating resistor R0, the first current limiting signal is output to the current limiting control unit 250, and when the current limiting end CL is open, the second current threshold is output to the current limiting control unit 250; the first end of the sixteenth MOS tube M16 is connected to the first end of the fifteenth MOS tube M15, and the sixteenth MO The control end of the S tube M16 is connected to the control end of the fifteenth MOS tube M15, the second end of the sixteenth MOS tube M16 is connected to the first end of the second resistor R2, the current flowing through the sixteenth MOS tube M16 is the second intermediate signal, the second end of the second resistor R2 is connected to the load output end OUT, the first end of the second resistor R2 is also connected to the second input end of the first comparator A1, the second intermediate signal corresponds to the first current limiting signal or the second current threshold, when the current limiting end CL is connected to the regulating resistor R0, the second intermediate signal corresponds to the first current limiting signal, for example, the second intermediate signal is proportional to the first current limiting signal, at this time the voltage of the first end of the second resistor R2 is the second reference threshold; when the current limiting end CL is open, the second intermediate signal corresponds to the second current threshold. In this embodiment, the number of the second current mirror is one, but the present application is not limited thereto. In other embodiments of the present application, the second current mirror may not be provided (see Figure 3b), at this time, the first current limiting signal or the second current threshold is directly or indirectly output to the second resistor R2, or the second current mirror also includes a second-first current mirror and a second-second current mirror, and the number of the second-first current mirror and the second-second current mirror is set as needed. When the second current mirror includes the second-first current mirror and the second-second current mirror, the connection method of the second-first current mirror is similar to or the same as the previous one, and the second end of the second-second current mirror is connected to the power ground terminal GND, and the first end of the second-second current mirror is connected to the second end of the fifteenth MOS tube M15 or the sixteenth MOS tube M16 or is used to output the second intermediate signal, so as to realize that the output current of the second current mirror is output to the second resistor R2 in a desired manner, which is a conventional technology in the field and will not be repeated here. In this embodiment, the fifteenth MOS tube M15 and the sixteenth MOS tube M16 are enhanced PMOS tubes, and the current flowing through the fifteenth MOS tube M15 is proportional to the current flowing through the sixteenth MOS tube M16, for example, the ratio between the two is 1:1, 2:1, 1:2, etc.

[0073] Generally speaking, since the adjustment resistor R0 is external, there is a certain probability that the factory will forget to connect the adjustment resistor R0, that is, the current limiting terminal CL is in an open circuit state. The current limiting terminal CL in an open circuit state will cause inconvenience to the normal use of the intelligent electronic switch 200. For example, the power switch M1 cannot be stably turned on when the load is 120. In order to solve this problem, please refer to Figure 2 and Figure 3a In this embodiment, the intelligent electronic switch 200 further includes an open circuit processing module 270, which is connected to the current limiting terminal CL and the current limiting generation module 230. When the open circuit processing module 270 detects that the current limiting terminal CL is in an open circuit state, it controls the current limiting generation module 230 to stop limiting the current of the power switch M1, and controls the preset second current threshold to limit the current of the power switch M1.

[0074] Specifically, in this embodiment, the open circuit processing module 270 includes an open circuit current generating module 271, an open circuit detection module 272 and a current switching module 273. The open circuit current generating module 271 is used to generate the second current threshold, and here, the open circuit current generating module 271 includes a current source, and the current source is used to directly or indirectly generate the second current threshold.

[0075] In this embodiment, the open circuit detection module 272 includes a pull-up branch 2711 and an open circuit detection unit 2712, wherein the pull-up branch 2711 is used to pull up the voltage of the current limiting terminal CL to a preset voltage when the current limiting terminal CL is open, which is the output voltage of the first internal power supply 260 in this case, so as to detect the open circuit of the current limiting terminal CL. In this embodiment, the pull-up branch 2711 includes a nineteenth MOS tube M19, a first end of the nineteenth MOS tube M19 is connected to the first internal power supply 260, a second end of the nineteenth MOS tube M19 is connected to the current limiting terminal CL, and a control end of the nineteenth MOS tube M19 is connected to a preset second bias voltage Vb. In this embodiment, regardless of whether the current limiting terminal CL is open, short-circuited, or connected to the adjustment resistor R0, by setting the second bias voltage Vb, the current of the nineteenth MOS tube M19 controlling the pull-up branch 2711 will be very small, and the current flowing through the nineteenth MOS tube M19 is almost constant, and its current value is The first current limiting signal when the resistance value of the regulating resistor R0 is 2 times less than or equal to the maximum allowed resistance value, that is, the current flowing through the nineteenth MOS tube M19 is 2 times less than or equal to the minimum allowed first current limiting signal, that is, the current value flowing through the nineteenth MOS tube M19 is less than or equal to half of the minimum allowed first current limiting signal, for example, 1 / 2, 1 / 3, 1 / 4, 1 / 5, 1 / 6, 1 / 7, 1 / 8, 1 / 9, 1 / 10, 1 / 20, 1 / 50, 1 / 100, etc. of the minimum allowed first current limiting signal can be reduced by such a setting. When the current limiting terminal CL is normally connected to the regulating resistor R0, the first current limiting signal is:

[0076] Vref1 / R0-I19;

[0077] Wherein, Vref1 is the voltage value of the first reference voltage, R0 is the resistance value of the adjustment resistor R0, and I19 is the constant current flowing through the nineteenth MOS transistor M19.

[0078] In this embodiment, it is assumed that the maximum allowable adjustment resistor R0 is connected, and the current flowing through the adjustment resistor R0 is Vref1 / R0, and the first current limiting signal is (Vref1 / R0-I19), so that the first current limiting signal is greater than or equal to Vref1 / 2R0. When the current flowing through the nineteenth MOS tube M19 causes I19 to change by 10% due to the manufacturing process or other factors, the influence of the change on the first current limiting signal is less than or equal to 5%. The smaller I19 is, the smaller the influence on the first current limiting signal is. Therefore, by setting the current value I19 flowing through the nineteenth MOS tube M19 to be smaller than the first current limiting signal, it is beneficial to reduce the influence on the first current limiting signal and reduce the influence on the linearity between the adjustment resistor R0 and the first current limiting signal. In addition, in other embodiments of the present application, the nineteenth MOS tube M19 can also be replaced with a current source, and the output current of the current source is also subject to the constraints of the previous conditions. In addition, in other embodiments of the present application, the nineteenth MOS tube M19 can also be replaced with a resistor. In this case, the current flowing through the resistor is also subject to the constraints of the previous conditions, but setting the resistor is not as good as the previous two implementation methods. The reason is that the resistor takes up more area in the chip, resulting in a higher chip cost, and the current flowing through the resistor is affected by the first internal power supply 260. When the output voltage of the first internal power supply 260 is not very stable, the current variation range on the pull-up branch 2711 will be relatively large, resulting in an increased impact on the first current limiting signal. However, the setting of the nineteenth MOS tube M19 and the current source does not have such a problem. In this embodiment, the nineteenth MOS tube M19 is an enhanced PMOS tube.

[0079] In this embodiment, the open circuit detection unit 2712 detects whether the current limiting terminal CL is in an open circuit state through the voltage of the current limiting terminal CL. When the voltage of the current limiting terminal CL is greater than or equal to the preset first voltage threshold, the open circuit detection unit 2712 determines that the current limiting terminal CL is in an open circuit state. The open circuit detection unit 2712 controls the current switching module 273 to control the current limiting generation module 230 to stop limiting the current of the power switch M1, and controls the second current threshold to limit the current of the power switch M1.

[0080] Specifically, in this embodiment, the open circuit detection unit 2712 includes a twentieth MOS transistor M20, a twenty-first MOS transistor M21, a sixty-second MOS transistor M62, and a sixty-third MOS transistor M63. Among them, the first end of the twentieth MOS transistor M20 is connected to the first internal power supply 260, the control end of the twentieth MOS transistor M20 is connected to the second end thereof, the second end of the twentieth MOS transistor M20 is connected to the first end of the twenty-first MOS transistor M21, the control end of the twenty-first MOS transistor M21 is connected to the current limiting end CL, and the second end of the twenty-first MOS transistor M21 is connected to the power grounding end GND; the first end of the sixty-second MOS transistor M62 is connected to the first internal power supply 260, the control end of the sixty-second MOS transistor M62 is connected to the second end of the twentieth MOS transistor M20, the second end of the sixty-second MOS transistor M62 is connected to the first end of the sixty-third MOS transistor M63, the control end of the sixty-third MOS transistor M63 is connected to the second end of the twentieth MOS transistor M20, and the second end of the sixty-third MOS transistor M63 is connected to the power grounding end GND. In this embodiment, the open circuit detection unit 2712 is actually a voltage comparator. The configuration of the voltage comparator is not limited to the open circuit detection unit 2712 of this embodiment (see Figure 3b ), those skilled in the art may also use other conventional circuits to form a voltage comparator to determine whether the current limiting terminal CL is open-circuited, and this application does not impose any limitation on this.

[0081] In this embodiment, the current switching module 273 includes a first switch tube K1 and a second switch tube K2, wherein a first end of the first switch tube K1 is connected to a first end of the second switch tube K2, the first end of the first switch tube K1 is also used to connect to the current limiting control unit 250, specifically connected to the second end of the fifteenth MOS tube M15, the second end of the first switch tube K1 is used to directly or indirectly access the first current limiting signal, the control end of the first switch tube K1 is connected to the open circuit detection unit 2712, specifically connected to the second end of the sixty-second MOS tube M62, the second end of the second switch tube K2 is used to directly or indirectly access the second The current threshold, the control end of the second switch tube K2 is also connected to the open circuit detection unit 2712, specifically connected to the second end of the sixty-second MOS tube M62, wherein when the second end of the sixty-second MOS tube M62 is connected to the voltage of the first internal power supply 260 (the sixty-second MOS tube M62 is turned on at this time), the second switch tube K2 is controlled to be turned on at this time, and the first switch tube K1 is turned off and cut off, when the second end of the sixty-second MOS tube M62 is connected to the voltage of the power ground terminal GND (the sixty-third MOS tube M63 is turned on at this time), the second switch tube K2 is controlled to be turned off and cut off at this time, and the first switch tube K1 is turned on. In this embodiment, the first switch tube K1 is an enhanced PMOS tube, and the second switch tube K2 is an enhanced NMOS tube. However, the present application is not limited to this. In other embodiments of the present application, the first switch tube K1 can also be an enhanced NMOS tube, and the second switch tube K2 can be an enhanced PMOS tube. At this time, an odd number of inverters are added between the second end of the sixty-second MOS tube M62 and the control end of the first switch tube K1 and the control end of the second switch tube K2.

[0082] In this embodiment, when the current limiting terminal CL is in a non-open circuit state, for example, the regulating resistor R0 is normally connected or short-circuited, the voltage of the current limiting terminal CL is equal to or less than the first reference voltage, and the first reference voltage is less than the first voltage threshold. At this time, the twenty-first MOS tube M21 is not turned on, or even if it is partially turned on, its pull-down capability is not as strong as the pull-up capability of the twentieth MOS tube M20, thereby causing the sixty-third MOS tube M63 to be turned on, the sixty-second MOS tube M62 to be turned off, and the voltage of the power ground terminal GND is output to the control terminal of the first switch tube K1, the control terminal of the sixth switch tube M63, and the control terminal of the seventh switch tube M64. At the control end of the second switch tube K2, the first switch tube K1 is controlled to be turned on by the open circuit detection unit 2712, and the second switch tube K2 is controlled to be turned off by the open circuit detection unit 2712. At this time, the current switching module 273 controls the output of the signal derived from the first current limiting signal to the current limiting control unit 250. If current limiting is required, the current limiting control unit 250 limits the current flowing through the power switch M1 based on the first current limiting signal, so that the current limiting generation module 230 acts on the current limiting of the power switch M1; when the current limiting terminal CL is in an open circuit state, the voltage of the current limiting terminal CL is pulled up. The branch 2711 quickly pulls up to the output voltage of the first internal power supply 260. During the rapid rise of the voltage at the current limiting terminal CL, the twenty-first MOS tube M21 is gradually turned on and then fully turned on, and its pull-down capability is changed from weak to strong. When the voltage at the current limiting terminal CL is greater than the first voltage threshold, the pull-down capability of the twenty-first MOS tube M21 is greater than the pull-up capability of the twentieth MOS tube M20. At this time, the sixty-second MOS tube M62 is turned on, and the sixty-third MOS tube M63 is turned off, so that the voltage of the first internal power supply 260 is output to the control terminal of the first switch tube K1. , the control end of the second switch tube K2. At this time, the first switch tube K1 is controlled by the open circuit detection unit 2712 to be disconnected and cut off, and the second switch tube K2 is controlled by the open circuit detection unit 2712 to be turned on and turned on. At this time, the current switching module 273 controls the output of the second current threshold to the current limiting control unit 250. If current limiting is required, the current limiting control unit 250 limits the current flowing through the power switch M1 based on the second current threshold, so that the open circuit current generating module 271 plays a role in limiting the current of the power switch M1. At this time, the current limiting generating module 230 does not play a role in limiting the current of the power switch M1.

[0083] In this embodiment, the 20th MOS tube M20 is a depletion type NMOS tube. Since the control end of the 20th MOS tube M20 is connected to its second end, the 20th MOS tube M20 is naturally turned on, and the 63rd MOS tube M63 is controlled to be turned on when the current limiting end CL is in a non-open state, so that the first switch tube K1 is turned on and the second switch tube K2 is turned off. In this embodiment, the 21st MOS tube M21 and the 63rd MOS tube M63 are enhanced NMOS tubes, and the 62nd MOS tube M62 is an enhanced PMOS tube. In addition, in other embodiments of the present application, the 20th MOS tube M20 can also be replaced by a resistor, but the resistor is more area-consuming in the chip, resulting in higher cost. In addition, in other embodiments of the present application, the 20th MOS tube M20 can also be replaced by a current source.

[0084] In this embodiment, an open circuit processing module 270 is added, and the open circuit processing module 270 is connected to the current limiting terminal CL, the current limiting generation module 230, and the current limiting control unit 250. When the open circuit processing module 270 detects that the current limiting terminal CL is open, it outputs a preset second current threshold, and controls the current limiting generation module 230 to stop limiting the current of the power switch M1. The current limiting control unit 250 is connected to the open circuit processing module 270. When the current flowing through the power switch M1 is greater than or equal to the third current limiting threshold, the current limiting control unit 250 limits the current flowing through the power switch M1. The third current limiting threshold corresponds to the first current limiting signal or the second current threshold. Therefore, when the current limiting terminal CL is in an open circuit state due to unintentional failure, the open circuit processing module 270 of the intelligent electronic switch 200 can detect this state and output a preset second current threshold to the current limiting control unit 250. At this time, the first current limiting signal does not work. The current limiting control unit 250 determines whether the current flowing through the power switch M1 is overcurrent based on the second current threshold. Therefore, even if the power switch M1 is loaded with a load 120, it can be normally turned on as required, and the open circuit of the current limiting terminal CL will not affect the normal use of the intelligent electronic switch 200.

[0085] In this embodiment, the second current threshold is equal to the first current limiting signal when the current limiting end CL is connected to the minimum adjustment resistor R0, but the present application is not limited thereto. In other embodiments of the present application, the second current threshold may also be other suitable values.

[0086] In this example, please continue to refer to Figure 3a, the switch control unit 220 includes a second internal power supply 221, which is connected to the power supply terminal VCC. The second internal power supply 221 is used to boost the voltage of the power supply terminal VCC. The second internal power supply 221 is, for example, a charge pump. In this embodiment, the first end of the fifteenth MOS tube M15 and the first end of the sixteenth MOS tube M16 are both connected to the second internal power supply 221. Generally speaking, the output voltage of the second internal power supply 221 is two times, three times, etc., of the voltage of the power supply terminal VCC. In this embodiment, the first internal power supply 260 is connected to the power supply terminal VCC. The first internal power supply 260 is used to step down the voltage of the power supply terminal VCC. The first internal power supply 260 is, for example, an LDO. In this embodiment, the output voltage of the first internal power supply 260 is generally 6V, 5V, etc., and those skilled in the art can set the desired output voltage according to actual needs. In addition, in other embodiments of the present application, the second internal power supply 221 may not be included in the switch control unit 220.

[0087] In addition, in other embodiments of the present application, please refer to Figure 1b , Figure 2 and Figure 3b When the power switch M1 is connected as a low-side switch, the principle is the same as Figure 3a In addition, here, the open circuit detection unit 2712 is a voltage comparator A2, and the specific implementation of the voltage comparator is not limited.

[0088] The embodiment of the present application further provides an integrated circuit chip, the integrated circuit chip includes the above-mentioned intelligent electronic switch 200, that is, the above-mentioned intelligent electronic switch 200 is made on the same semiconductor substrate. Among them, the power supply terminal VCC is a power supply pin, the power ground terminal GND is a power ground pin, the load output terminal OUT is a load output pin, and the current limiting terminal CL is a current limiting pin.

[0089] Other embodiments of the present application also provide a chip product, the chip product includes the above-mentioned intelligent electronic switch 200, wherein the components of the intelligent electronic switch 200 except the power switch M1 are located on the first integrated circuit chip, and the power switch M1 is located on the second integrated circuit chip, that is, the first integrated circuit chip is made on a semiconductor substrate, and the second integrated circuit chip is made on another semiconductor substrate. Among them, the power supply terminal VCC is the power supply pin, the power ground terminal GND is the power ground pin, the load output terminal OUT is the load output pin, the current limiting terminal CL is the current limiting pin, the power supply pin, the power ground pin, and the current limiting pin are located on the first integrated circuit chip, and the load output pin is located on the second integrated circuit chip. The first integrated circuit chip and the second integrated circuit chip can also be provided with other pins as needed. Here, the first integrated circuit chip and the second integrated circuit chip are packaged into one product.

[0090] In addition, in other embodiments of the present application, the intelligent electronic switch 200, integrated circuit chip, and chip product of the present embodiment are not limited to use in automotive electronics, but can also be used in industrial automation, aerospace and other fields.

[0091] Second embodiment

[0092] See also Figure 4 , Figure 4 This is a circuit module diagram of the intelligent electronic switch 200 connected to the adjustment resistor according to the second embodiment of the present application. This embodiment is similar to the first embodiment, so the parts not described in this embodiment can refer to the first embodiment. The main difference between this embodiment and the first embodiment is that the short circuit of the current limiting terminal CL is also processed.

[0093] Please refer to Figure 1a , Figure 4 and Figure 5In this embodiment, the current limiting generation module 230 further includes a first current mirror, which is used to convert the first current limiting signal into a corresponding first intermediate signal. The first intermediate signal may be equal to or different from the first current limiting signal. For example, the ratio of the first current limiting signal to the first intermediate signal is 1:1, 10:1, 100:1, 1000:1, 10000:1, etc., and the present application does not limit this. In this embodiment, the first current mirror includes a first-first current mirror, which includes a thirteenth MOS tube M13 and a fourteenth MOS tube M14, wherein the first end of the thirteenth MOS tube M13 is connected to the first internal power supply 260, the control end of the thirteenth MOS tube M13 is connected to the second end thereof, and the second end of the thirteenth MOS tube M13 is connected to the first end of the twelfth MOS tube M12; the first end of the fourteenth MOS tube M14 is connected to the first internal power supply 260, the control end of the fourteenth MOS tube M14 is connected to the control end of the thirteenth MOS tube M13, and the second end of the fourteenth MOS tube M14 is used to output the first intermediate signal. In this embodiment, the thirteenth MOS tube M13 and the fourteenth MOS tube M14 are enhanced PMOS tubes. In this embodiment, the number of the first current mirror is one, and the first end of the first current mirror (that is, the first end of the thirteenth MOS tube M13 and the fourteenth MOS tube M14) is connected to the first internal power supply 260, but the present application is not limited thereto. In other embodiments of the present application, the first current mirror may not be provided (for example, the first embodiment), or the first current mirror may further include the first current mirror and the first second current mirror, and the number of the first current mirror and the first second current mirror may be set as required. When the first current mirror includes the first current mirror and the first second current mirror, the connection mode of the first current mirror is similar to or the same as the above, the second end of the first second current mirror is connected to the power ground terminal GND, and the first end of the first second current mirror is connected to the second end of the thirteenth MOS tube M13 or the fourteenth MOS tube M14 or is used to output the first intermediate signal, so as to realize that the first current mirror outputs the first intermediate signal in a desired manner. This is a conventional technology in the art and will not be described in detail here.

[0094] Generally speaking, in addition to being open-circuited, the current limiting terminal CL is directly exposed. Due to various reasons, the current limiting terminal CL may be short-circuited with the power ground terminal GND, such as dirt, accidentally dropped metal components, etc. At this time, the open circuit processing module 270 will determine that the current limiting terminal CL is in a non-open circuit state, and the first current limiting signal will be extremely large. Correspondingly, the second reference threshold will also be very large, resulting in the failure of the current limiting protection of the intelligent electronic switch 200, resulting in possible damage to the intelligent electronic switch 200. In order to improve this problem, in this embodiment, the intelligent electronic switch 200 also includes a short circuit processing module 240, which is connected to the current limiting generation module 230 and the open circuit processing module 270. The short circuit processing module 240 is used to output the second current limiting signal and output it to the current limiting control unit 250 via the current switching module 273. The short circuit processing module 240 is also used to generate a preset first current threshold. In this embodiment, when the first current corresponding signal is greater than the first current threshold, it indicates that the current limiting terminal CL is likely to be short-circuited, and the second current limiting signal corresponds to the first current threshold. In this embodiment, the second current limiting signal is equal to the first current threshold. In other embodiments of the present application, the second current limiting signal is proportional to the first current threshold. Of course, the second current limiting signal can also be other preset values; when the first current corresponding signal is less than or equal to the first current threshold, it indicates that the first current limiting signal is normal. At this time, the second current limiting signal corresponds to the first current limiting signal. In this embodiment, the second current limiting signal is equal to the first current corresponding signal. In other embodiments of the present application, the second current limiting signal is proportional to the first current corresponding signal. In this embodiment, the first current corresponding signal corresponds to the first intermediate signal, for example, the first current corresponding signal is proportional to the first intermediate signal, and the ratio is, for example, 1:1, 1:2, etc.

[0095] Generally speaking, the product specification of the intelligent electronic switch 200 will limit the resistance range of the regulating resistor R0. According to the above description, the size of the first current limiting signal is (Vref1 / R0-I19). When the resistance value of the regulating resistor R0 is the minimum allowed, the first current limiting signal is the maximum. When the resistance value of the regulating resistor R0 is the maximum allowed, the first current limiting signal is the minimum. In the above description, the first current corresponding signal and the first current limiting signal are in a positive linear relationship, preferably in a positive proportional relationship. In this embodiment, the first current corresponding signal is compared with the first current threshold to determine whether the current limiting terminal CL is short-circuited. Specifically, when the first current corresponding signal is greater than the first current threshold, it indicates that the current of the current limiting terminal CL is very large and is likely to be short-circuited; when the first current corresponding signal is less than or equal to the first current threshold, it indicates that the first current limiting signal is normal, and the first current limiting signal is between the maximum and minimum allowed values, indicating that the current limiting terminal CL is normally connected to the regulating resistor R0. In this embodiment, the first current threshold is equal to the first current corresponding signal when the resistance value of the regulating resistor R0 is the minimum allowed.

[0096] In this embodiment, the current limiting control unit 250 is connected to the short-circuit processing module 240 via the open circuit processing module 270. The current limiting control unit 250 is used to receive the second current limiting signal or the second current threshold. When the current limiting end CL is connected to the adjusting resistor R0 or is short-circuited, the first switch tube K1 is turned on and the second switch tube K2 is turned off. On this basis, when the first current corresponding signal is less than or equal to the first current threshold, the second current limiting signal corresponds to the first current limiting signal. When the current flowing through the power switch M1 is greater than or equal to the third current limiting threshold, the current limiting control unit 250 limits the current flowing through the power switch M1. At this time, the third current limiting threshold corresponds to the second current limiting signal, that is, the third current limiting threshold corresponds to the second current limiting signal. The current threshold corresponds to the first current limiting signal; when the first current corresponding signal is greater than the first current threshold, the second current limiting signal corresponds to the first current threshold. When the current flowing through the power switch M1 is greater than or equal to the third current limiting threshold, the current limiting control unit 250 limits the current flowing through the power switch M1. At this time, the third current limiting threshold corresponds to the second current limiting signal, that is, the third current limiting threshold corresponds to the first current threshold. Since the first current threshold is artificially set, it will not be very large, so that current limiting protection can be effectively performed, improving the problem that the current limiting terminal CL is short-circuited in the related technology and cannot perform effective current limiting protection; when the current limiting terminal CL is open-circuited, the first switch tube K1 is disconnected and cut off, and the second switch tube K2 is turned on. In this embodiment, the current limiting control unit 250 limits the current flowing through the power switch M1. Specifically, the current limiting control unit 250 limits the current flowing through the power switch M1 to the third current limiting threshold. The third current limiting threshold is in a positive linear relationship with the second current limiting signal or the second current threshold, and preferably in a positive proportional relationship. In this embodiment, the third current limiting threshold and the second reference threshold are in a positive linear relationship, preferably in a positive proportional relationship.

[0097] In this embodiment, a short-circuit processing module 240 is added. The short-circuit processing module 240 outputs a second current limiting signal to the current limiting control unit 250 via the open-circuit processing module 270. When the first current corresponding signal is greater than the preset first current threshold, the second current limiting signal corresponds to the first current threshold; when the first current corresponding signal is less than or equal to the first current threshold, the second current limiting signal corresponds to the first current limiting signal; the current limiting control unit 250 is connected to the short-circuit processing module 240 via the open-circuit processing module 270. When the current flowing through the power switch M1 is greater than or equal to the third current limiting threshold, the current limiting control unit 250 limits the current flowing through the power switch M1. The third current limiting threshold corresponds to the second current limiting signal. Thus, when the current limiting terminal CL is normally connected to the regulating resistor R0, the first current corresponding signal will be less than or equal to the first current threshold, and the first current corresponding signal is used to determine whether the current flowing through the power switch M1 is overcurrent. When there is no overcurrent, the power switch M1 works normally. When the current flowing through the power switch M1 is judged to be overcurrent by the first current corresponding signal, the current limiting control unit 250 limits the current flowing through the power switch M1; when the current limiting terminal CL is accidentally short-circuited, the first current corresponding signal will be very large, and the first current corresponding signal will be greater than the first current threshold. The first current threshold is used to determine whether the current flowing through the power switch M1 is overcurrent. When there is no overcurrent, the power switch M1 works normally. When the current flowing through the power switch M1 is judged to be overcurrent by the first current threshold, the current limiting control unit 250 limits the current flowing through the power switch M1. Thus, when the current limiting terminal CL is short-circuited, the present embodiment can effectively perform current limiting protection, improve the problem that the current limiting terminal CL is short-circuited in the related art and cannot perform effective current limiting protection, thereby improving safety.

[0098] In this embodiment, the short-circuit processing module 240 includes a short-circuit current generating unit 241 and a second comparison and selection unit 242. The short-circuit current generating unit 241 is used to generate a first short-circuit current signal, wherein the first short-circuit current signal generating unit includes a current source, the current source is used to output the first short-circuit current signal, and the first short-circuit current signal is a current. In this embodiment, the second comparison and selection unit 242 is connected to the current switching module 273, the short-circuit current generating unit 241, and the current limiting generating module 230, the second comparison and selection unit 242 receives the first intermediate signal or the first current limiting signal, and is used to receive the first short-circuit current signal, the second comparison and selection unit 242 compares the first current corresponding signal with the first current threshold, wherein the first current corresponding signal is the same as the first intermediate signal or the first current limiting signal, or corresponds to the first intermediate signal or the first current limiting signal, in this embodiment, the first current corresponding signal corresponds to the first intermediate signal, for example, the ratio of the first current corresponding signal to the first intermediate signal is 1:1, 1:2, etc., the first current threshold is the same as or corresponds to the first short-circuit current signal, in this embodiment, the first current threshold corresponds to the first short-circuit current signal. In this embodiment, when the first current corresponding signal is greater than the first current threshold, the second comparison and selection unit 242 outputs a second current limiting signal, and the second current limiting signal is the same signal as the first current threshold; when the first current limiting signal is less than or equal to the first current threshold, the second comparison and selection unit 242 outputs a second current limiting signal, and the second current limiting signal is the same signal as the first current corresponding signal.

[0099] Specifically, in this embodiment, the second comparison and selection unit 242 includes a third-first current mirror and a third-second current mirror, wherein the third-first current mirror includes a ninth MOS tube M9 and a tenth MOS tube M10, wherein the first end of the ninth MOS tube M9 is connected to the second end of the fourteenth MOS tube M14 to receive the first intermediate signal, the control end of the ninth MOS tube M9 is connected to the first end thereof, the second end of the ninth MOS tube M9 is connected to the third-second current mirror, the second end of the tenth MOS tube M10 is connected to the third-second current mirror, the control end of the tenth MOS tube M10 is connected to the control end of the ninth MOS tube M9, and the first end of the tenth MOS tube M10 is connected to the second end of the fifteenth MOS tube M15 via the first switch tube K1 to output the second current limiting signal. In this embodiment, the current flowing through the ninth MOS tube M9 is equal to the current flowing through the fourteenth MOS tube M14, and the third-first current mirror converts the first intermediate signal into a first current corresponding signal. In this embodiment, the ninth MOS tube M9 and the tenth MOS tube M10 are enhanced NMOS tubes.

[0100] In this embodiment, the third second current mirror includes a seventh MOS tube M7, an eighth MOS tube M8 and an eleventh MOS tube M11. Among them, the first end of the seventh MOS tube M7 is connected to the first short-circuit current signal generating unit 241 to access the first short-circuit current signal, the control end of the seventh MOS tube M7 is connected to its first end, and the second end of the seventh MOS tube M7 is connected to the power ground terminal GND; the first end of the eighth MOS tube M8 is connected to the second end of the ninth MOS tube M9, the control end of the eighth MOS tube M8 is connected to the control end of the seventh MOS tube M7, and the second end of the eighth MOS tube M8 is connected to the power ground terminal GND; the first end of the eleventh MOS tube M11 is connected to the second end of the tenth MOS tube M10, the control end of the eleventh MOS tube M11 is connected to the control end of the seventh MOS tube M7, and the second end of the eleventh MOS tube M11 is connected to the power ground terminal GND. In this embodiment, the seventh MOS tube M7, the eighth MOS tube M8 and the eleventh MOS tube M11 are all enhanced NMOS tubes.

[0101] In this embodiment, the current flowing through the seventh MOS tube M7 is the first short-circuit current signal, and the seventh MOS tube M7 and the eleventh MOS tube M11 form a current mirror, so that the current flowing through the eleventh MOS tube M11 is proportional to the first short-circuit current signal, and the current flowing through the eleventh MOS tube M11 is the first current threshold. The current comparison principle of this embodiment is: when the first current corresponding signal is less than or equal to the first current threshold, the current signal output by the eleventh MOS tube M11 is limited by the first current corresponding signal, so that at this time, the second current limiting signal output by the circuit composed of the eleventh MOS tube M11 and the tenth MOS tube M10 is equal to the first current corresponding signal; when the first current corresponding signal is greater than the first current threshold, the current signal output by the tenth MOS tube M10 is limited by the first current threshold, so that at this time, the circuit composed of the eleventh MOS tube M11 and the tenth MOS tube M10 can only output the first current threshold, and cannot output a larger current, and the second current limiting signal is equal to the first current threshold. This embodiment realizes the comparison of two current signals through a smart circuit design. In this embodiment, the eighth MOS tube M8 is adapted to the eleventh MOS tube M11, so that the ninth MOS tube M9 and the tenth MOS tube M10 form a relatively ideal current mirror. Preferably, in this embodiment, the ratio of the width-to-length ratio of the eighth MOS tube M8 to the width-to-length ratio of the eleventh MOS tube M11 is equal to the ratio of the width-to-length ratio of the ninth MOS tube M9 to the width-to-length ratio of the tenth MOS tube M10. In other embodiments of the present application, the ratio of the width-to-length ratio of the eighth MOS tube M8 to the width-to-length ratio of the eleventh MOS tube M11 is greater than the ratio of the width-to-length ratio of the ninth MOS tube M9 to the width-to-length ratio of the tenth MOS tube M10. In this embodiment, the comparison of the signal is realized by the tenth MOS tube M10 and the eleventh MOS tube M11. In addition, in other embodiments of the present application, the comparison of the first current threshold and the first current corresponding signal can be realized by other methods and a lower signal can be output. In addition, in other embodiments of the present application, when the matching requirements are not too high, the third second current mirror may not include the eighth MOS tube M8.

[0102] In addition, when the current limiting terminal CL is short-circuited, the current flowing through the current limiting terminal CL and the current flowing through the fourteenth MOS transistor M14 may be very large, which may cause the intelligent electronic switch 200 to heat up seriously, and may affect the life and safety of the intelligent electronic switch 200. In order to solve this problem, in this embodiment, the current limiting generation module 230 also includes a first current limiting element 231, and the first current limiting element 231 is located on the line where the twelfth MOS transistor M12 and the thirteenth MOS transistor M13 are located. For example, the first end of the twelfth MOS transistor M12 is connected to the second end of the first current limiting element 231, and the first end of the first current limiting element 231 is connected to the second end of the thirteenth MOS transistor M13. The first current limiting element 231 is used to limit the current flowing through the current limiting terminal CL to prevent the first current limiting signal from being too large; and the current limiting element 231 and the regulating resistor R0 are located on the same branch, and the current is limited at the source when short-circuited, which can minimize the impact on the intelligent electronic switch. In this embodiment, the first current limiting element 231 is the eighteenth MOS transistor M18, and the eighteenth MOS transistor M18 is an enhanced PMOS transistor. In addition, in other embodiments of the present application, the first current limiting element 231 may also be a resistor.

[0103] In this embodiment, the first current limiting element 231 is a MOS tube, which has more advantages than a resistor, which is discussed below. Generally speaking, when the first current limiting element 231 is a resistor, when the voltage output by the first internal power supply 260 is relatively low, the resistor needs to occupy a relatively high voltage, resulting in the current limiting terminal CL being unable to normally output the first reference voltage; in addition, the first current limiting resistor will occupy a relatively large area on the chip, which is not conducive to cost reduction; and when the current limiting terminal CL is short-circuited, the twelfth MOS tube M12 is turned on and used as a switch, and the voltage drop on the thirteenth MOS tube M13 is generally about 1V, and the current flowing through the resistor is (5V / resistance value of the resistor) , assuming that the output voltage of the first internal power supply 260 is 6V), the current at this time must be greater than the first current limiting signal when the resistance value of the regulating resistor R0 is the minimum allowed value, which facilitates the distinction of subsequent signals. However, since the current flowing through the resistor is greatly affected by the voltage output by the first internal power supply 260, when the output voltage of the first internal power supply 260 fluctuates greatly, the current flowing through the current limiting resistor may be within the range of the minimum first current limiting signal and the maximum first current limiting signal when the current limiting terminal CL is short-circuited, resulting in the inability to correctly identify that the current limiting terminal CL is short-circuited.

[0104] In the present embodiment, the first current limiting element 231 is the eighteenth MOS tube M18, and the control end of the eighteenth MOS tube M18 is connected to the first bias voltage Va. When the current limiting end CL is normally connected to the adjustment resistor R0, the eighteenth MOS tube M18 is used as a switch and is in a conducting state, and will not affect the first current limiting signal. When the current limiting end CL is short-circuited, the twelfth MOS tube M12 is used as a switch and is in a conducting state, and the eighteenth MOS tube M18 will enter a saturated state, and the eighteenth MOS tube M18 limits the current flowing through it. At this time, the first current limiting signal is affected by the first bias voltage Va (the source of the eighteenth MOS tube M18 is approximately equal to The voltage of the first internal power supply 260), and the current flowing through the eighteenth MOS tube M18 when it is in a saturated state is greater than the first current limiting signal when the resistance value of the regulating resistor R0 is the minimum allowed. In addition, considering the possible deviation of the eighteenth MOS tube M18 due to factors such as the manufacturing process, the current flowing through the eighteenth MOS tube M18 when it is in a saturated state is 50% greater than the first current limiting signal when the resistance value of the regulating resistor R0 is the minimum allowed, preferably 1 times greater, so that even if the eighteenth MOS tube M18 has a large manufacturing error, the saturation current will not be less than the maximum allowed first current limiting signal, and will not affect the normal use of the current limiting terminal CL connected to the regulating resistor R0. In addition, the current flowing through the eighteenth MOS tube M18 when it is in a saturated state cannot be too large, otherwise it will also generate serious heat and affect the service life of the chip. The current flowing through the eighteenth MOS tube M18 when it is in a saturated state is less than 10 times the first current limiting signal when the resistance value of the regulating resistor R0 is the minimum allowed. Preferably, the current flowing through the eighteenth MOS tube M18 when it is in a saturated state is less than 5 times the first current limiting signal when the resistance value of the regulating resistor R0 is the minimum allowed. In this embodiment, the advantages of setting the first current limiting element 231 as a MOS tube rather than setting a resistor are as follows: when the eighteenth MOS tube M18 is in a saturated state, the current flowing through it is less affected by the output voltage of the first internal power supply 260, the saturation current value is relatively stable, and the area of ​​the eighteenth MOS tube M18 is very small relative to the resistor, which is conducive to reducing costs.

[0105] Third embodiment

[0106] See also Figure 6 , Figure 6 1 is a circuit module diagram of an intelligent electronic switch 200 connected to an adjustable resistor according to a third embodiment of the present application. This embodiment is similar to the second embodiment, so the parts not described in this embodiment may refer to the second embodiment. The main difference between this embodiment and the second embodiment is that the open circuit processing module includes a short circuit processing module.

[0107] Please refer to Figure 1a , Figure 6 and Figure 7aIn this embodiment, the open circuit processing module 270 includes an open circuit detection module 272 and a current switching module 273. The open circuit processing module 270 of this embodiment also includes a short circuit processing module 240. The open circuit processing module 270 of this embodiment does not include the open circuit current generating module 271 of the second embodiment, but generates a first current threshold through the short circuit processing module 240. The first current threshold of this embodiment is the second current threshold of the second embodiment, that is, in this embodiment, the two are the same signal, so that through such processing, there is no need to generate the second current threshold through the open circuit current generating module 271, which can reduce the number of components and reduce costs. In this embodiment, the current switching module 273 includes a seventeenth switch tube K17, the first end of the seventeenth switch tube K17 is connected to the first end of the tenth MOS tube M10, the second end of the seventeenth switch tube K17 is connected to the second end of the tenth MOS tube M10, and the control end of the seventeenth switch tube K17 is connected to the open circuit detection unit 2712, specifically connected to the second end of the sixty-second MOS tube M62.

[0108] In this embodiment, when the current limiting terminal CL is normally connected to the regulating resistor R0, the sixty-third MOS tube M63 is turned on, the sixty-second MOS tube M62 is turned off, and the voltage of the power ground terminal GND (that is, the second open circuit signal) is output to the control end of the seventeenth switch tube K17. The seventeenth switch tube K17 is controlled to be turned off by the open circuit detection unit 2712. At the same time, the second comparison and selection unit 242 of the short circuit processing module 240 selects the first current corresponding signal as the second current limiting signal. At this time, the open circuit processing module 270 controls the output of the first current corresponding signal to the current limiting control unit 250, that is, the current limiting control unit The signal of the element 250 is derived from the first current limiting signal. If current limiting is required, the current limiting control unit 250 limits the current flowing through the power switch M1 based on the first current corresponding signal, so that the current limiting generation module 230 acts on the current limiting of the power switch M1; when the current limiting terminal CL is short-circuited, the voltage of the current limiting terminal CL is 0V or close to 0V, and similarly, the sixty-third MOS tube M63 is turned on, the sixty-second MOS tube M62 is turned off, and the voltage of the power ground terminal GND (that is, the second open circuit signal) is output to the control end of the seventeenth switch tube K17, and the seventeenth switch tube K17 is detected by the open circuit detection unit 2 712 controls the disconnection and cut-off, and at the same time, the second comparison and selection unit 242 of the short-circuit processing module 240 selects the first current threshold as the second current limiting signal, and the open-circuit processing module 270 controls the output of the first current threshold to the current limiting control unit 250. If current limiting is required, the current limiting control unit 250 limits the current flowing through the power switch M1 based on the first current threshold, so that the short-circuit processing module 240 acts on the current limiting of the power switch M1; when the current limiting terminal CL is in an open-circuit state, at this time, the sixty-second MOS tube M62 is turned on, and the sixty-third MOS tube M63 is turned off, so that the current of the first internal power supply 260 is The voltage (that is, the first open-circuit signal) is output to the control end of the seventeenth switch tube K17. At this time, the seventeenth switch tube K17 is controlled by the open-circuit detection unit 2712 to be turned on, so that the seventeenth switch tube K17 short-circuits the tenth MOS tube M10. At this time, the open-circuit processing module 270 controls the output of the second current threshold (which is the same signal as the first current threshold) to the current limiting control unit 250. If current limiting is required, the current limiting control unit 250 limits the current flowing through the power switch M1 based on the second current threshold, so that the short-circuit processing module 240 of the open-circuit processing module 270 plays a role in limiting the current of the power switch M1.

[0109] In this embodiment, the second current threshold and the first current threshold are set to be the same signal, and both are generated by the short-circuit processing module 240. By such a setting, the number of components and the occupied area can be reduced, and the cost can be reduced. Moreover, in this embodiment, the seventeenth switch tube K17 is cleverly set, and the two ends of the seventeenth switch tube K17 are correspondingly connected to the two ends of the tenth MOS tube M10. The seventeenth switch tube K17 determines whether to output the first current corresponding signal or the first current threshold to the current limiting control unit 250 based on the control of the open circuit detection unit 2712. By such a setting, the compatibility of the processing of the open circuit state and the processing of the short circuit state can be achieved, and the circuit design is very simple.

[0110] In this embodiment, the seventeenth switch tube K17 is an enhanced NMOS tube, but the present application is not limited to this. In other embodiments of the present application, the seventeenth switch tube K17 can also be an enhanced PMOS tube, or other types of switch tubes. In this case, other circuits, such as inverters, can be added between the control end of the seventeenth switch and the second end of the sixty-second MOS tube M62 as needed.

[0111] In addition, in other embodiments of the present application, see Figure 7bThe first end of the seventeenth switch tube K17 is connected to the first end of the fourteenth MOS tube M14 via the current source 2732, that is, connected to the first internal power supply 260, the second end of the seventeenth switch tube K17 is connected to the second end of the fourteenth MOS tube M14, and the control end of the seventeenth switch tube K17 is connected to the open circuit detection unit 2712, so that the seventeenth switch tube K17 can determine whether the signal derived from the first current limiting signal works. Specifically, when the current limiting end CL is in an open circuit state, the open circuit detection unit 2712 controls the seventeenth switch tube K17 to turn on. The current of the series current source 2732 is output to the ninth MOS tube M9, the second current threshold is the lower of the current from the current source and the signal from the first short-circuit current signal, and the second current threshold is output to the current limiting control unit 250. When the current limiting terminal CL is in a non-open circuit state, for example, the current limiting terminal CL is normally connected to the adjustment resistor R0 or the current limiting terminal CL is short-circuited, the open circuit detection unit 2712 controls the seventeenth switch tube K17 to be disconnected and cut off, and the first current corresponding signal or the first current threshold is output to the current limiting control unit 250. Here, the seventeenth switch tube K17 is an enhanced PMOS tube, and the open circuit detection unit 2712 also includes an inverter, one end of the inverter is connected to the second end of the sixty-second MOS tube M62, and the other end of the inverter is connected to the control end of the seventeenth switch tube K17. Here, the current source of the seventeenth switch tube K17 can also be not provided, and the first end of the seventeenth switch tube K17 is connected to the first end of the fourteenth MOS tube M14, and the current is limited by the eighth MOS tube M8. In addition, in other embodiments of the present application, the eighth MOS transistor M8 may not be provided, and the current flowing through the ninth MOS transistor is limited and determined by the current source 2732. Here, the current source 2732 can realize the definition of the desired current output.

[0112] In the first to third embodiments, when the current limiting terminal CL is in an open circuit state, the current limiting terminal CL may be interfered with by an abnormal signal, which may cause the voltage of the current limiting terminal CL to drop. For example, when the voltage of the current limiting terminal CL drops to 1V in a short time due to interference, the open circuit processing module 270 will quickly control the first current corresponding signal to take effect, which is undesirable. In order to improve this problem, the present application provides a fourth embodiment.

[0113] Fourth embodiment

[0114] See also Figure 8 , Figure 8 2 is a partial circuit module diagram of an intelligent electronic switch 200 according to a fourth embodiment of the present application. This embodiment is similar to the third embodiment, so the parts not described in this embodiment may refer to the third embodiment. The main difference between this embodiment and the third embodiment is the open circuit detection unit 2712.

[0115] Please refer to Figure 1a, Figure 6 and Figure 8 In this embodiment, when the open circuit detection unit 2712 determines that the current limiting terminal CL changes from an open circuit state to a non-open circuit state based on the voltage of the current limiting terminal CL, the open circuit detection unit 2712 delays outputting a second open circuit signal to the current switching module 273. The current switching module 273 receives the second open circuit signal and controls the output of the first current corresponding signal to the current limiting control unit 250. The third current limiting threshold corresponds to the first current corresponding signal.

[0116] In this embodiment, one way for the open circuit detection unit 2712 to delay the output of the second open circuit signal is: the open circuit detection unit 2712 also includes a first capacitor C1 and a second current limiting element 274, the first capacitor C1 is used to store energy, and the second current limiting element 274 is used to limit the discharge current of the first capacitor C1, so that the first capacitor C1 needs a certain delay time to discharge to the preset threshold voltage. In this embodiment, when the open circuit detection unit 2712 determines that the current limiting end CL is changed from an open circuit state to a non-open circuit state due to the interference signal, the first capacitor C1 is discharged through the current limiting of the second current limiting element 274, and the open circuit detection unit 2712 still outputs the first open circuit signal. When the first capacitor C1 is discharged for a period of time, resulting in the voltage on the first capacitor C1 being less than the preset threshold voltage, the open circuit detection unit 2712 changes from outputting the first open circuit signal to outputting the second open circuit signal, and the period of discharge is the delay time. Generally speaking, the duration that the interference signal maintains a lower voltage is shorter than the delay duration. Therefore, this embodiment can improve the impact of the interference signal on the current limiting protection after such processing; when the current limiting terminal CL is indeed connected to the adjustment resistor R0, it can switch back to the signal derived from the first current limiting signal after the delay duration.

[0117] Specifically, in the present embodiment, the open circuit detection unit 2712 further includes a twenty-second MOS transistor M22, a twenty-third MOS transistor M23, a twenty-fourth MOS transistor M24, and a twenty-fifth MOS transistor M25, wherein a first end of the twenty-second MOS transistor M22 is connected to the first internal power supply 260, a second end of the twenty-second MOS transistor M22 is connected to a first end of the twenty-third MOS transistor M23, a second end of the twenty-third MOS transistor M23 is connected to a power ground terminal GND, a control end of the twenty-second MOS transistor M22 and a control end of the twenty-third MOS transistor M23 are both connected to a first end of the first capacitor C1, a first end of the first capacitor C1 is connected to a second end of a sixty-second MOS transistor M62, The second end of the first capacitor C1 is connected to the power ground terminal GND; the first end of the twenty-fourth MOS tube M24 is connected to the first internal power supply 260, the second end of the twenty-fourth MOS tube M24 is connected to its control end, the second end of the twenty-fourth MOS tube M24 is also connected to the first end of the twenty-fifth MOS tube M25 and the control end of the seventeenth switch tube K17, the second end of the twenty-fifth MOS tube M25 is connected to the power ground terminal GND, and the control end of the twenty-fifth MOS tube M25 is connected to the second end of the twenty-second MOS tube M22; the first end of the second current limiting element 274 is connected to the second end of the sixty-third MOS tube M63, and the second end of the second current limiting element 274 is connected to the power ground terminal GND. In addition, in other embodiments of the present application, the positions of the second current limiting element 274 and the sixty-third MOS tube M63 can also be interchanged.

[0118] In the present embodiment, when the current limiting terminal CL is in an open circuit state, the voltage of the current limiting terminal CL is quickly pulled to the output voltage of the first internal power supply 260 by the pull-up branch 2711. During the voltage rise of the current limiting terminal CL, the twenty-first MOS tube M21 is disconnected and cut off, gradually turned on, and then becomes fully turned on, and its pull-down capability changes from weak to strong. When the voltage of the current limiting terminal CL is greater than the first voltage threshold, the pull-down capability of the twenty-first MOS tube M21 is greater than the pull-up capability of the twentieth MOS tube M20. At this time, the sixty-second MOS tube M62 is turned on, and the sixty-third MOS tube M63 is turned off, so that the voltage of the first internal power supply 260 is output to the first capacitor C1, and the first capacitor C1 is quickly charged to the output voltage of the first internal power supply 260, so that the twenty-third MOS tube M23 is turned on, which causes the twenty-fifth MOS tube M25 to be disconnected and cut off, and the voltage of the first internal power supply 260 is output to the first capacitor C1. The first capacitor C1 is quickly charged to the output voltage of the first internal power supply 260, so that the twenty-third MOS tube M23 is turned on, which causes the twenty-fifth MOS tube M25 to be turned off, and the voltage of the first internal power supply 260 is output to the first capacitor C1. The output voltage is output to the seventeenth switch tube K17 via the twenty-fourth MOS tube M24, and the seventeenth switch tube K17 is turned on; when the current limiting end CL changes from an open circuit state to a non-open circuit state, for example, due to signal interference and the like, the voltage of the current limiting end CL is less than the first voltage threshold, and the twenty-first MOS tube M21 is not turned on, or even if it is turned on, its pull-down capability is not as strong as the pull-up capability of the twentieth MOS tube M20, thereby causing the sixty-third MOS tube M63 to be turned on, the sixty-second MOS tube M62 to be turned off, and the voltage on the first capacitor C1 to be discharged via the second current limiting element 274. After a period of discharge, which is the delay time, the twenty-second MOS tube M22 changes from being turned off to being turned on, the twenty-third MOS tube M23 changes from being turned on to being turned off, and then the twenty-fifth MOS tube M25 is turned on, and thus the seventeenth switch tube K17 is turned off. Thus, when the current limiting end CL is disturbed by a signal and changes from an open circuit state to a non-open circuit state, the open circuit detection unit 2712 will not immediately control the seventeenth switch tube K17 to be disconnected and cut off, but will need to delay for a period of time before controlling the seventeenth switch tube K17 to be disconnected and cut off. Such a setting can prevent problems such as current limiting failure and incorrect disconnection of the seventeenth switch tube K17 caused by signal interference, which is beneficial to improving the safety of the intelligent electronic switch 200.

[0119] In this embodiment, the twenty-second MOS tube M22 is an enhanced PMOS tube, the twenty-fourth MOS tube M24 is a depletion NMOS tube, and the twenty-third MOS tube M23 and the twenty-fifth MOS tube M25 are both enhanced NMOS. In addition, in other embodiments of the present application, the twentieth MOS tube M20 and the twenty-fourth MOS tube M24 can be replaced with pull-up resistors. In addition, in other embodiments of the present application, the output end of the open circuit detection module 272 can also include an even number of inverters as needed. In addition, in other embodiments of the present application, the twenty-second MOS tube M22-the twenty-fifth MOS tube M25 may not be provided, and at this time the first end of the first capacitor C1 is connected to the control end of the seventeenth switch tube K17.

[0120] In this embodiment, the second current limiting element 274 is a twenty-sixth MOS tube M26, the control end of the twenty-sixth MOS tube M26 is connected to the third bias voltage Vc, the current flowing through the twenty-sixth MOS tube M26 is controlled by the third bias voltage Vc, the maximum current flowing through the twenty-sixth MOS tube M26 is its saturation current, and when the first capacitor C1 is discharged, the current at this time is the saturation current of the twenty-sixth MOS tube M26. In addition, in other embodiments of the present application, the second current limiting element 274 can also be a current source or a resistor, and the relevant description of the first current limiting element 231 can be referred to, which will not be repeated here.

[0121] Fifth embodiment

[0122] See also Fig. 9 , Fig. 9 1 is a partial circuit module diagram of an intelligent electronic switch 200 according to a fourth embodiment of the present application. This embodiment is similar to the first embodiment, so the parts not described in this embodiment may refer to the first embodiment. The main difference between this embodiment and the first embodiment is the open circuit processing module 270.

[0123] Please refer to Figure 1a , Fig. 9 and Fig.10In this embodiment, the open circuit processing module 270 includes an open circuit detection module 272 and a current switching module 273, wherein the open circuit detection module 272 includes a pull-up branch 2711 and an open circuit detection unit 2712. In this embodiment, the open circuit detection unit 2712 is a voltage comparator, and the current switching module 273 includes a threshold current branch, a first end of the threshold current branch is connected to the current limiting end CL, and a second end of the threshold current branch is connected to the power ground end. The threshold current branch includes a fifth switch K5 and a fifth resistor R5, and the fifth switch K5 and the fifth resistor R5 are connected in series. In the figure, the first end of the fifth resistor R5 is connected to the current limiting end, the second end of the fifth resistor is connected to the first end of the fifth switch, and the second end of the fifth switch is connected to the power ground end, or the positions of the fifth switch and the fifth resistor are swapped. In this embodiment, when the open circuit detection unit 2712 determines that the current limiting terminal CL is in an open circuit state based on the voltage of the current limiting terminal CL, the open circuit detection unit 2712 outputs a first open circuit signal to the current switching module 273, and the fifth switch K5 is turned on. At this time, the current flowing through the fifth resistor is:

[0124] Vref1 / R5;

[0125] Wherein, Vref1 is the voltage value of the first reference voltage, and R5 is the resistance value of the fifth resistor R5. In this embodiment, there is a certain difference between the second current threshold and the current flowing through the fifth resistor R5 (the difference is known), specifically, the current flowing through the fifth resistor R5 minus the current flowing through the pull-up branch 2711.

[0126] In this embodiment, when the fifth switch is turned on, since the preset fifth resistor R5 is connected, the voltage of the current limiting end CL becomes the voltage value of the first reference voltage, and the open circuit detection unit 2712 will output a second open circuit signal. The open circuit detection unit 2712 will mistakenly determine that the current limiting end is not open. In order to improve this problem, in this embodiment, when the current switching module 273 receives the first open circuit signal, the fifth switch K5 is locked and turned on. The method of locking and turning on, for example, the current switching module 273 includes a trigger and the like. Similarly, when the current limiting terminal CL is normally connected to the regulating resistor R0, the voltage of the current limiting terminal is still the voltage value of the first reference voltage. In this embodiment, the open circuit detection module 272 cannot detect that the current limiting terminal changes from an open circuit state to a non-open circuit state. In order to solve this problem, in this embodiment, the current switching module 273 also includes a third comparator A3 and a logic processing unit 2731, wherein the logic processing unit 2731 includes a trigger, and the trigger is used to receive the first open circuit signal to lock and control the fifth switch to turn on. The first input terminal of the third comparator A3 is connected to a signal derived from the second current threshold, and the second input terminal of the third comparator A3 is connected to a reference signal, wherein the signal at the second input terminal of the third comparator A3 is 10% larger than the signal at its first input terminal, preferably 20% or 30% larger, so that it is not easy to misjudge.

[0127] In this embodiment, the third comparator may be a current comparator, and the current switching module 273 further includes an eighty-first MOS transistor, wherein the first end of the eighty-first MOS transistor is connected to the first end of the fifteenth MOS transistor, the second end of the eighty-first MOS transistor is connected to the first input end of the third comparator, and the control end of the eighty-first MOS transistor is connected to the control end of the fifteenth MOS transistor, so that the eighty-first MOS transistor and the fifteenth MOS transistor form a current mirror, and the output current of the second end of the eighty-first MOS transistor is derived from the second current threshold value; in this embodiment, the signal of the second input end of the third comparator A3 is also a current signal, and when the current limiting end is not connected to the regulating resistor R0, the signal of the first input end of the third comparator is less than the signal of the second input end thereof, and when the current limiting end is connected to the regulating resistor R0, the current flowing through the current limiting end CL increases, and then by design, the signal of the second input end of the third comparator A3 will be less than the signal of the first input end thereof, and at this time, it indicates that the current limiting end is changed from an open circuit state to a non-open circuit state, and the signal is output to the logic processing unit, and thereafter, the lock on the conduction of the fifth switch K5 is released, and the fifth switch K5 is disconnected and cut off. In addition, in other embodiments of the present application, the third comparator can also be a voltage comparator. In this case, the signal at the first input terminal of the third comparator A3 is a voltage, which is converted from the second current threshold. Converting current into voltage is a conventional technology in the field, and the signal at the second input terminal of the third comparator A3 is also a voltage. Similarly, the signal at the second input terminal of the third comparator A3 is 10% larger than the signal at its first input terminal, preferably 20% or 30% larger, so that it is not easy to misjudge.

[0128] In this embodiment, when the logic processing unit 2731 does not receive the first open-circuit signal, the third comparator A3 stops working; when the logic processing unit 2731 receives the first open-circuit signal, the third comparator is enabled, and the logic processing unit 2731 determines whether the current limiting end is changed from an open-circuit state to a non-open-circuit state based on the signal of the third comparator A3; when the signal at the first input end of the third comparator A3 is greater than the signal at its second input end, after the logic processing unit 2731 receives the signal, the logic processing unit 2731 controls the third comparator not to work thereafter or the third comparator A3 itself does not work, and then the logic processing unit 2731 controls the third comparator A3 to resume working only after receiving the first open-circuit signal again. In addition, in other embodiments of the present application, the third comparator 2731 can work all the time. When the logic processing unit 2731 does not receive the first open-circuit signal, the logic processing unit 2731 discards or does not process the signal output by the third comparator A3 (the signal from the output end of the third comparator is an invalid signal at this time). After the logic processing unit 2731 receives the first open-circuit signal, the logic processing unit 2731 determines whether the current limiting end is changed from an open-circuit state to a non-open-circuit state based on the signal of the third comparator A3 (the signal from the output end of the third comparator is a valid signal at this time). When the signal at the first input end of the third comparator A3 is greater than the signal at its second input end, the logic processing unit 2731 discards or does not process the signal output by the third comparator A3.

[0129] In this embodiment, when the current limiting end is in an open circuit state, the original current limiting generation module is used to generate a second current threshold, and the second current threshold is jointly generated by the current limiting generation module and the open circuit processing module 270, so that the intelligent electronic switch can also achieve normal operation.

[0130] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0131] It should be understood that the "plurality" mentioned in this article refers to two or more. Those skilled in the art will easily think of other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary technical means in the art that are not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present application are indicated by the following claims.

[0132] It should be noted that each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other. For the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0133] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. An intelligent electronic switch for processing an open circuit at a current limiting end, characterized in that: include: A power supply terminal, a power ground terminal, a load output terminal, a current limiting terminal, and a switch control unit, wherein the power supply terminal is used to connect to the positive electrode of the power supply, the power ground terminal is used to connect to the negative electrode of the power supply, the load output terminal is used to connect to the load, and the current limiting terminal is used to connect to the regulating resistor; A power switch, a first end of which is connected to a power supply end or a power ground end, a second end of which is connected to a load output end, and a control end of which is connected to a switch control unit, the switch control unit being used to control the power switch to be turned on or off; a current limiting generating module connected to the current limiting end, wherein the current limiting generating module generates a corresponding first current limiting signal based on the resistance value of the regulating resistor, and when the current limiting end is open, the current limiting generating module stops generating the first current limiting signal; an open circuit processing module, which is connected to the current limiting end, and outputs a preset second current threshold when the open circuit processing module detects that the current limiting end is open circuit; A current limiting control unit, which is connected to the open circuit processing module or the current limiting generation module, and when the current flowing through the power switch is greater than or equal to a third current limiting threshold, the current limiting control unit limits the current flowing through the power switch, and the third current limiting threshold corresponds to the first current limiting signal or the second current threshold.

2. The intelligent electronic switch according to claim 1, characterized in that: When the open circuit processing module detects that the current limiting terminal is open circuit, it controls the current limiting generation module to stop limiting the current of the power switch; The open circuit processing module includes an open circuit detection module and a current switching module; The open circuit detection module is connected to the current limiting end and the current switching module. The open circuit detection module determines whether the current limiting end is open based on the voltage of the current limiting end. When the open circuit detection module determines that the current limiting end is in an open circuit state, it outputs a first open circuit signal to the current switching module, and the current switching module receives the first open circuit signal and controls the output of the second current threshold to the current limiting control unit; when the open circuit detection module determines that the current limiting end is in a non-open circuit state, it outputs a second open circuit signal to the current switching module, and the current switching module receives the second open circuit signal and controls the output of a signal derived from the first current limiting signal to the current limiting control unit.

3. The intelligent electronic switch according to claim 2, characterized in that: The open circuit processing module includes a short circuit processing module, the short circuit processing module includes a short circuit current generating unit and a second comparison and selection unit, the second comparison and selection unit is connected to the short circuit current generating unit and the current limiting generating module, the short circuit current generating unit is used to generate a first short circuit current signal, and the second comparison and selection unit converts the first short circuit current signal into a first current threshold; Among them, when the current switching module receives the first open-circuit signal, it controls the output of the second current threshold to the current limiting control unit; when the current switching module receives the second open-circuit signal, it controls the output of the first current threshold or a signal derived from the first current limiting signal to the current limiting control unit, and the first current threshold and the second current threshold are the same signal.

4. The intelligent electronic switch according to claim 3, characterized in that: The second comparison and selection unit includes a third-first current mirror and a third-second current mirror, wherein the third-first current mirror is connected to the current limiting generation module, and the third-second current mirror is connected to the short-circuit current generation unit; The third-first current mirror is used to mirror the current flowing through the current limiting generation module to obtain a first current corresponding signal, the third-second current mirror mirrors the first short-circuit current signal to obtain a first current threshold, the third-first current mirror includes a tenth MOS transistor, the third-second current mirror includes an eleventh MOS transistor, the tenth MOS transistor is connected in series with the eleventh MOS transistor, the tenth MOS transistor is used to output the first current corresponding signal, the eleventh MOS transistor is used to output the first current threshold, the tenth MOS transistor and the eleventh MOS transistor work together to output the smaller of the first current corresponding signal and the first current threshold, wherein the first current corresponding signal corresponds to the first current limiting signal; When the current switching module receives the first open-circuit signal, the current switching module controls the first current limiting signal to stop being output to the third current mirror or short-circuits the source and drain of the tenth MOS tube.

5. The intelligent electronic switch according to claim 4, characterized in that: The current limiting generation module includes a first current mirror, and the first current mirror converts the first current limiting signal into a first intermediate signal and outputs it to a third current mirror; The first current mirror includes a thirteenth MOS tube and a fourteenth MOS tube, wherein a first end of the thirteenth MOS tube is connected to the first internal power supply, a control end of the thirteenth MOS tube is connected to a second end thereof, and the second end of the thirteenth MOS tube is used to access a first current limiting signal; a first end of the fourteenth MOS tube is connected to the first internal power supply, a control end of the fourteenth MOS tube is connected to a control end of the thirteenth MOS tube, and a second end of the fourteenth MOS tube is used to output a first intermediate signal; The third-first current mirror includes a ninth MOS tube and a tenth MOS tube, wherein the first end of the ninth MOS tube is connected to the second end of the fourteenth MOS tube to receive the first intermediate signal, the control end of the ninth MOS tube is connected to the first end thereof, the second end of the ninth MOS tube is connected to the third-second current mirror, the second end of the tenth MOS tube is connected to the third-second current mirror, the control end of the tenth MOS tube is connected to the control end of the ninth MOS tube, and the first end of the tenth MOS tube is used to output the first current corresponding signal, and the first current corresponding signal corresponds to the first intermediate signal; The third second current mirror includes a seventh MOS tube, an eighth MOS tube and an eleventh MOS tube, wherein the first end of the seventh MOS tube is connected to the short-circuit current generating unit to access the first short-circuit current signal, the control end of the seventh MOS tube is connected to the first end thereof, and the second end of the seventh MOS tube is connected to the power ground terminal; the first end of the eighth MOS tube is connected to the second end of the ninth MOS tube, the control end of the eighth MOS tube is connected to the control end of the seventh MOS tube, and the second end of the eighth MOS tube is connected to the power ground terminal; the first end of the eleventh MOS tube is connected to the second end of the tenth MOS tube, the control end of the eleventh MOS tube is connected to the control end of the seventh MOS tube, and the second end of the eleventh MOS tube is connected to the power ground terminal; The current switching module includes a seventeenth switch tube, two ends of the seventeenth switch tube are correspondingly connected to two ends of the tenth MOS tube, and the control end of the seventeenth switch tube is used to receive the first open circuit signal or the second open circuit signal. When the seventeenth switch tube receives the first open circuit signal, the seventeenth switch tube is turned on to short-circuit the tenth MOS tube or the fourteenth MOS tube; or, The current switching module includes a seventeenth switch tube and a current source, the seventeenth switch tube is connected in series with the current source, the two ends of the series branch are correspondingly connected to the two ends of the fourteenth MOS tube, the control end of the seventeenth switch tube is used to receive the first open circuit signal or the second open circuit signal, and when the seventeenth switch tube receives the first open circuit signal, the seventeenth switch tube is turned on.

6. The intelligent electronic switch according to claim 2, characterized in that: When the open circuit detection module determines that the current limiting end changes from an open circuit state to a non-open circuit state, the open circuit detection module delays outputting a second open circuit signal to the current switching module.

7. The intelligent electronic switch according to claim 6, characterized in that: The open circuit detection module includes a capacitor and a second current limiting element. When the open circuit detection module determines that the current limiting end changes from an open circuit state to a non-open circuit state, the capacitor is discharged through the second current limiting element. When the voltage on the capacitor is discharged to be less than a preset threshold voltage, the open circuit detection module outputs a second open circuit signal to the current switching module.

8. The intelligent electronic switch according to claim 1, characterized in that: The open circuit processing module includes an open circuit detection module and a current switching module, wherein the open circuit detection module is used to determine whether the current limiting end is open circuit, and the open circuit detection module is connected to the current switching module; The current switching module comprises a threshold current branch, a first end of the threshold current branch is connected to the current limiting end, a second end of the threshold current branch is connected to the power ground end, and the threshold current branch comprises a fifth switch and a fifth resistor connected in series; When the open circuit detection module detects that the current limiting terminal is open circuit, it outputs a first open circuit signal to the current switching module, and the current switching module controls the fifth switch to be locked and turned on to generate the second current threshold through the current limiting generation module.

9. The intelligent electronic switch according to claim 8, characterized in that: The current switching module includes a logic processing unit and a third comparator, the logic processing unit is connected to the open circuit detection module and the output end of the third comparator, the first input end of the third comparator is connected to the signal derived from the second current threshold, and the second input end of the third comparator is connected to the reference signal, and the reference signal is greater than the signal derived from the second current threshold; When the signal at the first input terminal of the third comparator is greater than the signal at the second input terminal thereof, the logic processing unit controls the fifth switch to be turned off.

10. The intelligent electronic switch according to any one of claims 1 to 9, characterized in that: The open circuit processing module includes a pull-up branch, one end of which is connected to the first internal power supply, and the other end of which is connected to the current limiting end. When the current limiting end is in an open circuit state, the pull-up branch pulls up the voltage of the current limiting end to the voltage of the first internal power supply.

11. The intelligent electronic switch according to claim 10, characterized in that: The maximum output current of the pull-up branch is less than half of the minimum first current limiting signal allowed to flow through the current limiting end, wherein the minimum first current limiting signal allowed to flow through the current limiting end corresponds to the first current limiting signal when the maximum adjustment resistance allowed to be connected to the current limiting end.

12. The intelligent electronic switch according to any one of claims 1 to 9, characterized in that: When the current flowing through the power switch is greater than or equal to the third current limiting threshold, the current limiting control unit controls the current flowing through the power switch to be equal to the third current limiting threshold; or, The current limiting generating module includes an operational amplifier and a twelfth MOS tube, wherein a first input terminal of the operational amplifier is connected to a first reference voltage, a second input terminal of the operational amplifier is connected to the current limiting terminal, an output terminal of the operational amplifier is connected to a control terminal of the twelfth MOS tube, a first terminal of the twelfth MOS tube is used to output a first current limiting signal, a second terminal of the twelfth MOS tube is connected to the current limiting terminal, wherein the first current limiting signal is less than a ratio of the first reference voltage to the regulating resistor.

13. An integrated circuit chip, characterized in that: It comprises the intelligent electronic switch as claimed in any one of claims 1 to 12, wherein the power supply end is a power supply pin, the power ground end is a power ground pin, the load output end is a load output pin, and the current limiting end is a current limiting pin.

14. A chip product, characterized in that: The intelligent electronic switch according to any one of claims 1 to 12, wherein the components of the intelligent electronic switch except the power switch are located on a first integrated circuit chip, and the power switch is located on a second integrated circuit chip; Among them, the power supply end is a power supply pin, the power ground end is a power ground pin, the load output end is a load output pin, the current limiting end is a current limiting pin, the power supply pin, the power ground pin, and the current limiting pin are located on a first integrated circuit chip, and the load output pin is located on a second integrated circuit chip.

15. An electromechanical device, characterized in that: The intelligent electronic switch according to any one of claims 1 to 12, the integrated circuit chip according to claim 13, or the chip product according to claim 14; It also includes a power supply, an adjusting resistor, a load and a microprocessor, wherein the positive pole of the power supply is connected to the power supply terminal, the negative pole of the power supply is connected to the power ground terminal, one end of the load is connected to the load output terminal, the other end of the load is connected to the power ground terminal or the power supply terminal, the microprocessor is connected to the intelligent electronic switch, the first end of the adjusting resistor is connected to the current limiting terminal, and the second end of the adjusting resistor is connected to the power ground terminal.

16. The electromechanical device according to claim 15, characterized in that The electromechanical device includes an automobile.

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