Intelligent electronic switch capable of reducing power, chip, chip product and electromechanical equipment

Abstract

The invention provides an intelligent electronic switch capable of reducing power, and the switch comprises a current limiting end which is used for connecting an adjusting resistor; a power switch; the current limiting generation module outputs a corresponding first current limiting signal based on the resistance value of the adjusting resistor; the voltage regulation module is connected with the first end and the second end of the power switch to obtain drain-source voltage and is further connected with the current limiting generation module, the voltage regulation module outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal, the second current limiting signal is smaller than a signal from the first current limiting signal, and the larger the drain-source voltage is, the smaller the second current limiting signal is. The second current limiting signal is smaller; and the current-limiting control unit is connected with the voltage regulation module, and when the current flowing through the power switch is greater than or equal to a third current-limiting threshold value, the current-limiting control unit limits the current flowing through the power switch. The embodiment of 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, a chip, a chip product and an electromechanical device for reducing power. 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] When the regulating resistor connected to the current limiting end is determined, the current limiting value of the intelligent electronic switch is determined. When the current flowing through the power switch reaches a value corresponding to the current limiting value, the current of the power switch is controlled to be limited, thereby providing safety protection. However, the inventor of the present application found that when the voltage across the source and drain of the power switch is large, even if the current limiting protection is performed, the intelligent electronic switch is still likely to be damaged. The inventor found that the intelligent electronic switch is burned out because the heat generated by the power switch is too large. Summary of the invention

[0005] The technical problem to be solved by the embodiments of the present application is to provide a power-reducing intelligent electronic switch, chip, chip product and electromechanical device to address the deficiencies of the prior art. The current limit value can be adjusted according to the drain-source voltage of the power switch to reduce the probability of the intelligent electronic switch being burned out.

[0006] In order to solve the above technical problems, the first aspect of the embodiment of the present application provides an intelligent electronic switch for reducing heat generation, including:

[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, which is connected to the current limiting end, and the current limiting generating module outputs a corresponding first current limiting signal based on the resistance value of the regulating resistor;

[0010] a voltage regulating module, connected to the first end and the second end of the power switch to obtain a drain-source voltage, and further connected to the current limiting generating module, wherein the voltage regulating module outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal, wherein the second current limiting signal is smaller than a signal derived from the first current limiting signal, wherein the larger the drain-source voltage is, the smaller the second current limiting signal is;

[0011] A current limiting control unit is connected to the voltage regulating 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 second current limiting signal.

[0012] Optionally, the voltage regulation module includes a voltage-current conversion module and an operation unit, the voltage-current conversion module is connected to the first end and the second end of the power switch to convert the drain-source voltage into a corresponding first conversion current signal, the operation unit is connected to the voltage-current conversion module and the current limiting generation module, and the operation unit outputs the second current limiting signal based on the first conversion current signal and the first current limiting signal.

[0013] Optionally, the second current limiting signal is obtained by subtracting a signal derived from the first current limiting signal from a signal derived from the first conversion current signal.

[0014] Optionally, within the voltage upper limit of the intelligent electronic switch, the power on the power switch is constantly smaller than the protection power.

[0015] Optionally, the voltage regulation module includes a voltage-current conversion module, a reference upper limit current generating unit, and an operation unit. The voltage-current conversion module is connected to the first end and the second end of the power switch to convert the drain-source voltage into a corresponding first conversion current signal. The reference upper limit current generating unit is used to generate a first preset current signal. The operation unit is connected to the voltage-current conversion module and the reference upper limit current generating unit. The operation unit operates the first preset current signal and a signal derived from the first conversion current signal to output a third conversion current signal, wherein the product of the drain-source voltage and the signal derived from the third conversion current signal is less than the protection power, and when the signal derived from the first current limiting signal is greater than the signal derived from the third conversion current signal, the second current limiting signal corresponds to the third conversion current signal.

[0016] Optionally, the third conversion current signal is obtained through subtraction calculation.

[0017] Optionally, the voltage regulation module includes a power limit comparison unit, the power limit comparison unit is connected to the current limit generation module, the current limit control unit, and the operation unit, the power limit comparison unit includes a first current mirror and a second current mirror, wherein the first current mirror is connected to the current limit generation module and the current limit control unit, and the second current mirror is connected to the first current mirror and connected to the third conversion current signal;

[0018] Among them, the first current mirror is used to mirror the current flowing through the current limiting generating module to obtain a first current corresponding signal, and the second current mirror mirrors the third conversion current signal to obtain a fourth conversion current signal. The first current corresponding signal and the fourth conversion current signal are located on the same current path. When the first current corresponding signal is greater than the fourth conversion current signal, the fourth conversion current signal is selected to correspond to the second current limiting signal.

[0019] Optionally, the first current mirror includes a ninth MOS tube and a tenth MOS tube, and the second current mirror includes a seventh MOS tube, an eighth MOS tube and an eleventh MOS tube;

[0020] Wherein, the first end of the ninth MOS tube is connected to the current limiting generating module, the second end of the ninth MOS tube is connected to the first end of the eighth MOS tube, the control end of the ninth MOS tube is connected to the first end thereof, the control end of the tenth MOS tube is connected to the control end of the ninth MOS tube, the first end of the tenth MOS tube is used to output a second current limiting signal, and the second end of the tenth MOS tube is connected to the first end of the eleventh MOS tube;

[0021] The control end of the eighth MOS tube is connected to the control end of the seventh MOS tube, the first end of the seventh MOS tube is connected to its control end, the first end of the seventh MOS tube is also connected to the third conversion current signal, the control end of the eleventh MOS tube is connected to the control end of the eighth MOS tube, and the second end of the seventh MOS tube, the second end of the eighth MOS tube, and the second end of the eleventh MOS tube are all connected to the power ground terminal.

[0022] Optionally, when the drain-source voltage is greater than a first preset voltage and less than a second preset voltage, the voltage regulating module outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal, and the more the drain-source voltage is greater than the first preset voltage, the smaller the second current limiting signal or the maximum value of the second current limiting signal.

[0023] 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.

[0024] 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;

[0025] 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.

[0026] 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;

[0027] 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.

[0028] Optionally, the electromechanical device includes a car.

[0029] The intelligent electronic switch in this embodiment includes a voltage regulating module, which is connected to the first end and the second end of the power switch to obtain a drain-source voltage, and is also connected to a current limiting generation module, wherein the voltage regulating module outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal, wherein the second current limiting signal is smaller than the signal derived from the first current limiting signal, wherein the larger the drain-source voltage, the smaller the second current limiting signal. Thus, by such processing, the power on the power switch can be reduced compared to before when the current limiting condition is triggered, and then the heat generated on the power switch can be reduced when the current limiting condition is triggered, so that the intelligent electronic switch is not easily damaged while achieving current limiting. Moreover, by connecting regulating resistors of different resistance values ​​to the current limiting end, it can be adapted to a variety of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] 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.

[0031] Figure 1a is a circuit module diagram of an electronic device according to a first embodiment of the present application;

[0032] Figure 1b is a circuit module diagram of an electronic device according to another embodiment of the present application;

[0033] 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;

[0034] Figure 3a is a detailed circuit module diagram of the intelligent electronic switch of the first embodiment of the present application;

[0035] Figure 3b is a detailed circuit module diagram of an intelligent electronic switch according to another embodiment of the present application;

[0036] Figure 4 is a detailed circuit module diagram of the intelligent electronic switch of the second embodiment of the present application;

[0037] Figure 5a is a detailed circuit module diagram of the intelligent electronic switch of the third embodiment of the present application;

[0038] Figure 5b is a detailed circuit module diagram of the voltage regulation module of the third embodiment of the present application;

[0039] Figure 6It is a curve diagram of the maximum power and the protection power on the power switch of the third embodiment of the present application. DETAILED DESCRIPTION

[0040] 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.

[0041] 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 may optionally include steps or units that are not listed, or may optionally include 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, and indirect connection means that other electronic components, pins, etc. may exist between the two connected components. The XX end mentioned in this application may be an actual terminal, or it may not be an actual terminal, such as only one end of a component or one end of a wire. The three situations mentioned in this application and / or include, such as A and / or B, include A, B, A and B. The signal derived from the XX signal or the signal corresponding to the XX signal mentioned in this application may be the XX signal itself, or it may be a signal obtained by converting the XX signal, such as a signal obtained by mirroring the XX signal once or multiple times.

[0042] First embodiment

[0043] The present application embodiment provides an electromechanical device, such as an automobile, medical equipment, industrial automation equipment, aerospace equipment, etc. Figure 1aThe 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 can also be other types of batteries or power supplies, such as AC / DC (alternating current / direct current) converters, DC / DC (direct current / direct current) converters, etc. 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 for one or more wiper systems. The capacitive load 120 is, for example, a lighting element, such as a xenon arc lamp, etc. 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.

[0044] 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, a parallel anti-reverse connection diode and a current limiting resistor may be provided between the power ground terminal GND and the negative electrode of the power supply 110.

[0045] 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 NMOS tube, a PMOS tube, a junction FET or an IGBT, etc. The 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).

[0046] 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.

[0047] Please refer to Figure 1a , Figure 2 , 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 outputs 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.

[0048] 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 Vref1, and the first reference voltage Vref1 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, and the second terminal of the twelfth MOS tube M12 is connected to the current limiting terminal CL. In the present embodiment, the twelfth MOS tube M12 is an 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 also equal to the first reference voltage Vref1, and the current flowing through the regulating resistor R0 is:

[0049] Vref1 / R0;

[0050] Wherein, Vref1 is the voltage value of the first reference voltage Vref1, and R0 is the resistance value of the regulating resistor R0. In this embodiment, the current flowing through the twelfth MOS tube M12 is equal to the current flowing through the regulating resistor R0. However, the present application is not limited thereto. In other embodiments of the present application, the current flowing through the twelfth MOS tube M12 may also have a certain difference from the current flowing through the regulating resistor R0, and the difference is generally known, and the difference will be very small and generally can be ignored.

[0051] In this embodiment, the current limiting generating module 230 also includes a first current mirror, which is used to convert the signal flowing through the twelfth MOS tube M12 into a corresponding first current limiting signal and output it. The first current limiting signal may be equal to the current flowing through the twelfth MOS tube M12, or may be unequal. For example, the ratio of the current flowing through the twelfth MOS tube M12 to the first current limiting signal is 1:1, 10:1, 100:1, 1000:1, 10000:1, etc., and the present application does not impose any limitation on this. In this embodiment, the first current mirror includes a first-first current mirror, and the first-first current mirror 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 its second end, 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 current limiting signal. In this embodiment, the thirteenth MOS tube M13 and the fourteenth MOS tube M14 are PMOS tubes. In the present embodiment, the number of first-one current mirrors 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 (when signal conversion or other processing is not required, the first current limiting signal is the current flowing through the twelfth MOS tube M12), or the first current mirror further includes a first-one current mirror and a first-two current mirror, and the number of the first-one current mirror and the first-two current mirror is set as needed. When the first current mirror includes the first-one current mirror and the first-two current mirror, the connection method of the first-one current mirror is similar to or the same as the previous one, the second end of the first-two current mirror is connected to the power ground terminal GND, and the first end of the first-two 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 current limiting signal, so as to realize that the first current mirror outputs the first current limiting signal in a desired manner. This is a conventional technology in the art and will not be repeated here.

[0052] 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 a third current limiting threshold, the current limiting control unit 250 limits the current flowing through the power switch M1.

[0053] In this embodiment, one implementation of the current limiting control unit 250 is shown in Figure 3a , the current limiting control unit 250 includes a current detection unit 251, a first comparator A1 and a third MOS tube M3. Among them, the current detection unit 251 is used to output a detection current signal, the detection current signal 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, the second input end of the first comparator A1 is used to connect the second reference 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, 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. In this embodiment, the first comparator A1 is a voltage comparator, and the current signal is detected. The second reference threshold is a voltage. Of course, those skilled in the art can also make adjustments as needed. In this embodiment, the third MOS tube M3 is an NMOS tube.

[0054] In this embodiment, the current detection unit 251 includes a second MOS transistor M2 and a first resistor R1, wherein the second MOS transistor M2 is a mirror transistor of the power switch M1, the type of the second MOS transistor M2 is the same as the type of the power switch M1, the current flowing through the second MOS transistor 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 transistor M2 is 100:1, 1000:1, 5000:1, 10000:1, etc., the control end of the second MOS transistor M2 is connected to the control end of the power switch M1, the first end of the second MOS transistor M2 is connected to the first end of the power switch M1, the second end of the second MOS transistor 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 transistor M2 is connected to the first input end of the first comparator A1, and the signal at the second end of the second MOS transistor M2 is the detection current signal, that is, the voltage at the first end of the first resistor R1. 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. This current detection method is a conventional technology in the field and will not be repeated here.

[0055] 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 a second current limiting signal (see the following description) 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 the present embodiment, the second current mirror includes a second-first current mirror, the second-first current mirror includes a fifteenth MOS transistor M15 and a sixteenth MOS transistor M16, wherein a first end of the fifteenth MOS transistor M15 is connected to the second internal power supply 221, a control end of the fifteenth MOS transistor M15 is connected to a second end thereof, and a second end of the fifteenth MOS transistor M15 is used to access a second current limiting signal; a first end of the sixteenth MOS transistor M16 is connected to a first end of the fifteenth MOS transistor M15, a control end of the sixteenth MOS transistor M16 is connected to a control end of the fifteenth MOS transistor M15, a second end of the sixteenth MOS transistor M16 is connected to a first end of a second resistor R2, a second end of the sixteenth MOS transistor M16 is used to output a second intermediate signal, a second end of the second resistor R2 is connected to a load output end OUT, a first end of the second resistor R2 is also connected to a second input end of the first comparator A1, the second intermediate signal corresponds to the second current limiting signal, and at this time, a voltage at the first end of the second resistor R2 is the second reference threshold. In this embodiment, the number of the second-first 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. In this case, the second current limiting signal is output to the second resistor R2, or the second current mirror also includes the second-first current mirror and the second-second current mirror. The number of the second-first current mirror and the second-second current mirror is set as required. When the second current mirror includes the second-first current mirror and the second-second current mirror, the connection mode of the second-first current mirror is similar to or the same as the previous one. 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. This is a conventional technology in the art and will not be described in detail here. In this embodiment, the fifteenth MOS tube M15 and the sixteenth MOS tube M16 are 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 of the two is 1:1, 2:1, 1:2, etc.

[0056] Generally speaking, when the adjustment resistor R0 is correctly connected to the current limiting terminal CL, the size of the first current limiting signal is determined. In the related art, the second current limiting signal is the same signal as the first current limiting signal, so that the second reference threshold remains unchanged. 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 current limiting control unit 250 will limit the current flowing through the power switch M1. However, the inventors of the present application have discovered that the voltage across the power switch M1 is changing dynamically, that is, the drain-source voltage of the power switch M1 is changing dynamically. The reasons for the change are, for example, different voltages of the connected power supply 110, for example, the voltage of the connected power supply 110 is 12V, 24V, 36V, etc., or the drain-source voltage increases due to short circuit or weak short circuit of the load 120. When the drain-source voltage is different, based on the same third current limiting threshold, the power on the power switch M1 will be different when the current limiting condition is triggered, and thus the heat generated by the power switch M1 will also be different. When the drain-source voltage of the power switch M1 is relatively large, the heat may be relatively serious when the current limiting protection is triggered, resulting in a greater probability of damage to the intelligent electronic switch 200, mainly burnt out.

[0057] In order to solve the above problems, the intelligent electronic switch 200 of the present application also includes a voltage regulating module 240, which is connected to the first end and the second end of the power switch M1 to obtain the drain-source voltage. The voltage regulating module 240 is also connected to the current limiting generation module 230 to obtain the first current limiting signal. The voltage regulating module 240 outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal. The second current limiting signal is smaller than the signal derived from the first current limiting signal. Therefore, the second current limiting signal is not only constrained by the first current limiting signal, but also constrained by the drain-source voltage. Moreover, the larger the drain-source voltage, the smaller the second current limiting signal, that is, the second current limiting signal changes dynamically with the drain-source voltage. The larger the drain-source voltage, the smaller the second current limiting signal, the smaller the drain-source voltage, and the larger the second current limiting signal. Therefore, by such processing, the power on the power switch M1 can be reduced compared with before when the current limiting condition is triggered, and then the heat generated on the power switch M1 can be reduced when the current limiting condition is triggered, so that the probability of the intelligent electronic switch 200 being damaged is reduced while the intelligent electronic switch 200 is realizing current limiting. Moreover, this embodiment can also adjust the first current limiting signal according to customer requirements, and then adjust the second current limiting signal, which is beneficial to improving the application range.

[0058] In this embodiment, the voltage regulating module 240 includes a voltage-current conversion module 241 and an operation unit, wherein the voltage-current conversion module 241 is respectively connected to the first end and the second end of the power switch M1 to obtain a drain-source voltage, and converts the drain-source voltage into a corresponding first conversion current signal, and the first conversion current signal is output to the operation unit, and the operation unit is connected to the voltage-current conversion module 241, the current limiting generation module 230, and the current limiting control unit 250. The operation unit receives the first current limiting signal and the first conversion current signal and performs operation to output a second current limiting signal, and the second current limiting signal is output to the current limiting control unit 250. In this embodiment, the second current limiting signal is equal to the difference between the first current limiting signal and the first conversion current signal, or the second current limiting signal is a signal corresponding to the difference between the first current limiting signal and the first conversion current signal, or the second current limiting signal is a signal corresponding to the difference between the first current limiting signal and the signal corresponding to the first conversion current signal. In this embodiment, the second current limiting signal is a signal corresponding to the difference between the first current limiting signal and the signal corresponding to the first conversion current signal. In this embodiment, the first conversion current signal is linearly related to the drain-source voltage. The larger the drain-source voltage is, the larger the first conversion current signal is, and the smaller the drain-source voltage is, the smaller the first conversion current signal is. The voltage-current conversion module 241 converts the drain-source voltage into the first conversion current signal, which is a conventional technology in the art and will not be described in detail here. The first conversion current signal is a current.

[0059] In this embodiment, the operation unit includes a current subtractor and a fourth current mirror, wherein the current subtractor is used to subtract the first conversion current signal from the first current limiting signal to obtain a difference, and the fourth current mirror is used to convert the difference into a second current limiting signal. In this embodiment, the current subtractor includes a thirty-sixth MOS tube M36 and a thirty-seventh MOS tube M37. The first end of the thirty-sixth MOS tube M36 is connected to the voltage-current conversion module 241 to obtain a first conversion current signal. The control end of the thirty-sixth MOS tube M36 is connected to its first end. The second end of the thirty-sixth MOS tube M36 is connected to the power ground terminal GND. The first end of the thirty-seventh MOS tube M37 is connected to the second end of the fourteenth MOS tube M14. The control end of the thirty-seventh MOS tube M37 is connected to the control end of the thirty-sixth MOS tube M36. The second end of the thirty-seventh MOS tube M37 is connected to the power ground terminal GND. The thirty-seventh MOS tube M37 and the thirty-sixth MOS tube M36 constitute a current mirror. The thirty-seventh MOS tube M37 outputs a second conversion current signal, which corresponds to the first conversion current signal. The output signal of the current subtractor is the difference between the first current limiting signal and the second conversion current signal and is output to the fourth current mirror. In this embodiment, the fourth current mirror includes a seventy-first MOS tube M71 and a seventy-second MOS tube M72, wherein the first end of the seventy-first MOS tube M71 is connected to the current subtractor to receive the difference, the control end of the seventy-first MOS tube M71 is connected to its first end, the second end of the seventy-first MOS tube M71 is connected to the power ground terminal GND, the first end of the seventy-second MOS tube M72 is used to output the second current limiting signal, the control end of the seventy-second MOS tube M72 is connected to the control end of the seventy-first MOS tube M71, and the second end of the seventy-second MOS tube M72 is connected to the power ground terminal GND. In this embodiment, the thirty-sixth MOS tube M36, the thirty-seventh MOS tube M37, the seventy-first MOS tube M71, and the seventy-second MOS tube M72 are all NMOS tubes. In addition, in other embodiments of the present application, the fourth current mirror may not be provided as needed, or more current mirrors may be provided to output the second current limiting signal to the current limiting control unit 250 in a desired manner.

[0060] In this example, please continue to refer to Figure 3aThe switch control unit 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.

[0061] 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 Similarly, those skilled in the art can implement the solution of the present invention through simple changes, which will not be described in detail here. In this case, the first internal power supply may not be required.

[0062] 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.

[0063] 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 of the power supply 110, 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.

[0064] In addition, in other embodiments of the present application, the intelligent electronic switch 200 and the integrated circuit chip of the present embodiment are not limited to use in automotive electronics, but can also be used in industrial automation, aerospace and other fields.

[0065] In this embodiment, regardless of the drain-source voltage of the power switch M1, the second current limiting signal is associated with the drain-source voltage.

[0066] However, in actual use, generally when the drain-source voltage is relatively large, it is likely to cause a relatively large power, which in turn may cause the power switch M1 to burn out. At this time, it is necessary to lower the second reference threshold to reduce power consumption and trigger the current limiting condition early. Otherwise, it may affect the drive of the load. For example, when the load is equivalent to a capacitor and a resistor in parallel, when the first current limiting signal is relatively small, the current is still reduced according to the drain-source voltage, which may cause the voltage on the capacitor to fail to rise. In order to better meet the actual application scenarios, the present application provides a second embodiment.

[0067] Second embodiment

[0068] See also Figure 4 , Figure 4 1 is a circuit module diagram of an intelligent electronic switch 200 according to a second 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 that the first current limiting signal is reduced based on the drain-source voltage only when the drain-source voltage is greater than the first preset voltage.

[0069] See also Figure 1a , Figure 2 , Figure 4In this embodiment, the current subtractor also includes a threshold current comparison unit. When the first conversion current signal is less than or equal to a preset first current threshold, it means that the drain-source voltage is less than or equal to the first preset voltage. At this time, the output second conversion current signal is 0, that is, the drain-source voltage does not affect the current limiting condition. When the first conversion current signal is greater than the first current threshold, it means that the drain-source voltage is greater than the first preset voltage. At this time, the output second conversion current signal is greater than 0. At this time, the second current limiting signal is equal to the signal corresponding to the difference between the first current limiting signal and the second conversion current signal.

[0070] Specifically, in this embodiment, the threshold current comparison unit includes a 40th MOS tube M40, a first end of the 40th MOS tube M40 is connected to the control end of the 36th MOS tube M36, a second end of the 40th MOS tube M40 is connected to the power ground GND, and the control end of the 40th MOS tube M40 is connected to the first bias voltage Vb1, wherein the first bias voltage Vb1 is used to control the maximum current flowing therethrough to be the first current threshold, that is, the saturation current value. In this embodiment, the 40th MOS tube M40 is an NMOS tube.

[0071] In this embodiment, when the first conversion current signal is less than or equal to the first current threshold, the first conversion current signal all flows out from the 40th MOS tube M40, and no current flows through the second end of the 36th MOS tube M36. At this time, the 36th MOS tube M36 is disconnected and cut off, so that the 37th MOS tube M37 is also disconnected and cut off, so that the first current limiting signal all flows into the 71st MOS tube M71, and will not be diverted to the 37th MOS tube M37; when the first conversion current signal is greater than the first current threshold, at this time, the current of the first conversion current signal greater than the first current threshold flows through the first end and the second end of the 36th MOS tube M36, and the current flows out from the 37th MOS tube M37 through the mirror, that is, the second conversion current signal is greater than 0, so that the current flowing into the 71st MOS tube M71 is the difference between the first current limiting signal and the second conversion current signal, and then after the mirror, the second current limiting signal is the signal corresponding to the difference.

[0072] In this embodiment, since the first conversion current signal represents the drain-source voltage of the power switch M1, the first current threshold is used to represent the first preset voltage corresponding to the drain-source voltage. When the drain-source voltage is greater than the first preset voltage, the first conversion current signal is greater than the first current threshold. The more the drain-source voltage is greater than the first preset voltage, the larger the second conversion current signal is, the smaller the difference is, and thus the smaller the second current limiting signal is.

[0073] The current subtractor of this embodiment includes a threshold current comparison unit. When the drain-source voltage is less than or equal to the first preset voltage, that is, the first conversion current signal is less than or equal to the first current threshold, the current limiting condition is not affected by the drain-source voltage. When the drain-source voltage is greater than the first preset voltage, that is, the first conversion current signal is greater than the first current threshold, the current limiting condition is affected by the drain-source voltage. For the same first current limiting signal, the more the drain-source voltage is greater than the first preset voltage, the smaller the second current limiting signal is, thereby reducing the probability of damage to the power switch M1. By setting in this way, when the drain-source voltage of the power switch M1 is relatively small, the drain-source voltage has no effect on the current limiting condition, and has no effect on the normal operation of the intelligent electronic switch 200, for example, the normal load capacity of the intelligent electronic switch 200 is not limited; when the drain-source voltage of the power switch M1 is relatively large, the drain-source voltage will affect the current limiting condition, thereby preventing the power switch M1 from being damaged due to severe heating.

[0074] The present embodiment also limits the maximum value of the second conversion current signal to prevent that when the adjustment resistor R0 is relatively large, the current limiting condition is triggered very early due to the relatively large drain-source voltage, and it may even cause the intelligent electronic switch 200 to be unable to be stably turned on (for example, the difference is 0). In order to improve this problem, in the present embodiment, the current subtractor also includes a maximum current limiting unit, which includes a thirty-eighth MOS tube M38. The first end of the thirty-eighth MOS tube M38 is connected to the second end of the thirty-seventh MOS tube M37, and the second end of the thirty-eighth MOS tube M38 is connected to the power ground terminal GND. The control end of the thirty-eighth MOS tube M38 is connected to the second bias voltage Vb2. The second bias voltage Vb2 is used to limit the maximum current value flowing through the thirty-eighth MOS tube M38. The maximum current value is defined as a second current threshold. When the second conversion current signal is greater than or equal to the second current threshold, it means that the drain-source voltage is greater than or equal to the second preset voltage, and the second preset voltage is greater than the first preset voltage. At this time, the second conversion current signal is the second current threshold. When the second conversion current signal is less than the second current threshold, it means that the drain-source voltage is less than the second preset voltage. At this time, the second conversion current signal remains unchanged. In this embodiment, the thirty-eighth MOS transistor M38 is an NMOS transistor. In this embodiment, the second bias voltage Vb2 and the first bias voltage Vb1 may be the same or different. When they are the same, the control end of the thirty-eighth MOS transistor M38 is connected to the control end of the fortieth MOS transistor M40, and both are connected to the first / second bias voltage Vb2.

[0075] In this embodiment, the current subtractor further includes a thirty-ninth MOS tube M39, the first end of the thirty-ninth MOS tube M39 is connected to the second end of the thirty-sixth MOS tube M36, the second end of the thirty-ninth MOS tube M39 is connected to the power ground terminal GND, and the control end of the thirty-ninth MOS tube M39 is connected to the second bias voltage Vb2. In this embodiment, the thirty-ninth MOS tube M39 is mainly for matching with the thirtieth MOS tube M30, so that the current mirror formed by the thirty-sixth MOS tube M36 and the thirty-seventh MOS tube M37 will be more ideal, and the corresponding relationship between the second conversion current signal and the first conversion current signal will be more ideal. In addition, in other embodiments of the present application, when the matching requirements are not too high, the thirty-ninth MOS tube M39 can be omitted.

[0076] In this embodiment, since an upper limit value is set for the second conversion current signal, when the current limiting terminal CL is connected normally, even if the drain-source voltage of the power switch M1 is relatively large, the probability that the difference between the first current limiting signal and the second conversion current signal is 0 is reduced, thereby reducing the impact on the normal use of the intelligent electronic switch 200.

[0077] In the above two embodiments, in order to increase the application range, the resistance range of the adjustment resistor R0 is relatively large, which will cause the range of the first current limiting signal to be relatively large. Since the second conversion current signal is only related to the drain-source voltage, the second conversion current signal may have limited influence on the first current limiting signal, and has little correlation with the power on the power switch M1, resulting in the power on the power switch M1 may still be relatively large. The above two embodiments have limited effect on improving the burnout of the power switch M1, or there is still a certain probability that the difference is 0, which will cause the second current limiting signal to be 0, causing the power switch M1 to be completely closed, and causing the power switch M1 to be unable to drive the load 120. In order to improve this problem, the present application provides a third embodiment.

[0078] Third embodiment

[0079] See also Figure 5a , Figure 5a 1 is a circuit module diagram of an intelligent electronic switch 200 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 to ensure that the power on the power switch M1 is not too large.

[0080] In this embodiment, the current limiting condition will be triggered as long as any of the following two conditions are met:

[0081] (1) A protection power is set. The protection power is obtained through experiments or theoretical calculations and is mainly used to protect the intelligent electronic switch 200 itself. The power on the power switch M1 should be less than the protection power to prevent the power switch M1 from being damaged due to heat. When the power on the power switch M1 is greater than the protection power, the power switch M1 is more likely to be damaged or its reliability will be reduced.

[0082] (2) When the current flowing through the power switch M1 is greater than or equal to the current from the first current limiting signal, the current limiting protection is triggered, which is set by the customer based on the requirements of the load 120 and the protection of the power switch M1.

[0083] In order to achieve both of the above functions, please refer to Figure 5a and Figure 5b In this embodiment, the voltage regulation module 240 also includes a reference upper limit current generating unit 243, and the reference upper limit current generating unit 243 includes a constant current source, which is used to generate a first preset current signal, and the first preset current signal corresponds to the preset upper limit current flowing through the power switch M1. The current subtractor is connected to the reference upper limit current generating unit 243 and is used to output a difference, which is referred to as a third conversion current signal here. The third conversion current signal is obtained by subtracting the second conversion current signal from the first preset current signal. In this embodiment, combined with the following description, the third conversion current signal represents the maximum power on the power switch M1, and reaching the third conversion current signal triggers the current limiting condition.

[0084] In this embodiment, the voltage regulation module 240 further includes a power limit comparison unit 244, which 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 current limiting 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 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 current limiting signal into a first current corresponding signal. In this embodiment, the ninth MOS tube M9 and the tenth MOS tube M10 are NMOS tubes.

[0085] 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 current subtractor to access the third conversion 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 NMOS tubes.

[0086] In this embodiment, the current flowing through the seventh MOS transistor M7 is the third conversion current signal. The seventh MOS transistor M7 and the eleventh MOS transistor M11 form a current mirror, so that the current flowing through the eleventh MOS transistor M11 is proportional to the third conversion current signal. Here, the current flowing through the eleventh MOS transistor M11 is called the fourth conversion current signal.

[0087] The current comparison principle of this embodiment is: when the first current corresponding signal is less than or equal to the fourth conversion current signal, 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 series circuit composed of the eleventh MOS tube M11 and the tenth MOS tube M10 is equal to the first current corresponding signal. At this time, the first current corresponding signal is constrained by the resistance value of the adjustment resistor R0, which is conducive to improving the application range; when the first current corresponding signal is greater than the fourth conversion current signal, the current signal output by the tenth MOS tube M10 is limited by the fourth conversion current signal, so that at this time, the series circuit composed of the eleventh MOS tube M11 and the tenth MOS tube M10 can only output the fourth conversion current signal, and cannot output a larger current. The second current limiting signal is equal to the fourth conversion current signal, which can ensure that it is less than the protection power. This embodiment realizes the comparison of two current signals through a smart and concise circuit design, and outputs a lower current signal. 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 the present 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 addition, in other embodiments of the present application, when the matching requirement is not too high, the third second current mirror may not include the eighth MOS tube M8. In addition, in other embodiments of the present application, those skilled in the art may also compare the two currents in other ways and select the lower current for output.

[0088] See below for details Figure 5a , Figure 5b , Figure 6 The power control of the present application is explained. In this embodiment, since the first preset current signal is preset and the first preset current signal is adjusted based on the drain-source voltage to obtain the third conversion current signal, the third conversion current signal can represent the maximum power flowing through the power switch M1.

[0089] Specifically, when the drain-source voltage of the power switch M1 is less than or equal to the first preset voltage, the second conversion current signal is 0, and the third conversion current signal is the first preset current signal, and corresponds to the preset upper limit current of the power switch M1. The preset upper limit current is the maximum current allowed to flow through the power switch M1. When the signal derived from the first current limiting signal is less than the signal derived from the third conversion current signal, that is, the first current corresponding signal is less than the fourth conversion current signal, the second current limiting signal corresponds to the first current limiting signal, and the maximum current allowed to flow through the power switch M1 is limited to less than the preset upper limit current (triggering the current limiting condition); when the first current corresponding signal is greater than or equal to the fourth conversion current signal, the second current limiting signal corresponds to the fourth conversion current signal, and the maximum current allowed to flow through the power switch M1 is the preset upper limit current (triggering the current limiting condition). Figure 6 It is obvious that when the drain-source voltage of the power switch M1 is less than or equal to the first preset voltage, the power on the power switch M1 is less than or equal to the product of the first preset voltage and the preset upper limit current (marked by 520), and the product is located on the lower left side of the protection power equal power curve (marked by 510), so it must be less than the protection power, which is beneficial to protect the power switch M1. Moreover, due to the setting of the preset upper limit current, the maximum value of the first current limiting signal can be limited to prevent the current at the current limiting end CL from being too large and exceeding the protection power, and the power switch M1 cannot be effectively protected. In addition, when the signal from the first current limiting signal is relatively small (corresponding to less than the preset upper limit current), the third current limiting threshold corresponds to the first current limiting signal, and the signal from the first current limiting signal is not processed, which can improve the load capacity and meet the user's expectations. The range of the first current limiting signal controlled by the adjustment resistor R0 is relatively wide, which is beneficial to improving the application range of the intelligent electronic switch.

[0090] When the drain-source voltage is greater than the first preset voltage and less than or equal to the second preset voltage, if the third conversion current signal is still equal to the first preset current signal, the power on the power switch M1 may be greater than the protection power. In order to avoid this situation, the present embodiment reduces the third conversion current signal as the drain-source voltage increases, and ensures that the power on the power switch M1 is less than the protection power by such processing. Specifically, when the drain-source voltage is greater than the first preset voltage and less than or equal to the second preset voltage, the second conversion current signal is greater than 0, and the larger the drain-source voltage, the larger the second conversion current signal, the smaller the difference between the first preset current signal and the second conversion current signal, that is, the smaller the third conversion current signal, the smaller the fourth conversion current signal; the smaller the drain-source voltage, the smaller the second conversion current signal, the larger the difference between the first preset current signal and the second conversion current signal, that is, the larger the third conversion current signal, the larger the fourth conversion current signal. When the signal derived from the first current limiting signal is smaller than the signal derived from the third conversion current signal, that is, the first current corresponding signal is smaller than the fourth conversion current signal, the second current limiting signal corresponds to the first current limiting signal, and the maximum current allowed to flow through the power switch M1 is limited to a signal smaller than the signal corresponding to the fourth conversion current signal; when the signal derived from the first current limiting signal is greater than or equal to the signal derived from the third conversion current signal, that is, the first current corresponding signal is greater than or equal to the fourth conversion current signal, the second current limiting signal corresponds to the fourth conversion current signal, and the maximum current allowed to flow through the power switch M1 is the signal corresponding to the fourth conversion current signal. Figure 6 It is obvious that when the drain-source voltage of the power switch M1 is greater than the first preset voltage and less than or equal to the second preset voltage, the maximum power allowed on the power switch M1 (the point on the oblique line) is located on the lower left side of the protection power equal power curve by controlling the third conversion current signal, so that the maximum power allowed on the power switch M1 must be less than the protection power, which is beneficial to protecting the power switch M1. In this embodiment, Figure 6 The oblique line between the first preset voltage and the second preset voltage may be a straight line, an upward convex curve, a downward concave curve, etc.

[0091] When the drain-source voltage is greater than the second preset voltage and less than the voltage upper limit value allowed by the specification (that is, the maximum voltage allowed by the power supply 110), the second conversion current signal remains unchanged thereafter, and is constantly equal to the second conversion current information when the drain-source voltage is the second preset voltage, that is, the third conversion current signal and the fourth conversion current signal remain unchanged, and the current on the power switch M1 corresponding to the fourth conversion current signal at this time is the preset lower limit current. As the drain-source voltage of the power switch M1 gradually increases, the power on the power switch M1 will also gradually increase. When the drain-source voltage of the power switch M1 reaches the voltage upper limit value, the maximum power on the power switch M1 at this time is the product of the voltage upper limit value and the corresponding third conversion current signal (which remains unchanged), from Figure 6 It can be seen that the maximum power is located on the lower left side of the protection power and other power curves, so that the power on the power switch M1 will be less than the protection power, which is beneficial to protecting the power switch M1. Moreover, since the preset lower limit current of the power switch M1 is set, the drain-source voltage can be prevented from further increasing, causing the third conversion current signal to become smaller and smaller, and finally causing the third conversion current signal to be 0. Although this can also prevent the power switch M1 from being damaged due to the relatively large power, it may also cause the power switch M1 to be unable to be used, or cause the power switch M1 to have a relatively weak load capacity (the current allowed to flow is very small). At this time, the power switch M1 still has a certain load capacity. When the drain-source voltage is greater than or equal to the voltage upper limit value allowed by the specification (that is, the maximum voltage allowed by the power supply 110), the power switch M1 will be controlled to be turned off, which is beneficial to protecting the power switch M1.

[0092] In this embodiment, the difference between the second preset voltage and the first preset voltage is less than the first preset voltage, and the difference is preferably less than 1 / 2 of the first preset voltage. By setting in this way, the complexity can be reduced. In this embodiment, the difference between the voltage upper limit value and the second preset voltage is also less than 1 / 2 of the first preset voltage. In this embodiment, the preset lower limit current is 1 / 2 of the preset upper limit current.

[0093] Generally speaking, when the intelligent electronic switch 200 is determined, the protection power of the general power switch M1 is determined, and then the protection power can be obtained according to the needs. Figure 6 In the curve 520, in the curve 520, the product of the first preset voltage and the preset upper limit current is the maximum power when the drain-source voltage is less than or equal to the first preset voltage, which is generally 5% or more less than the protection power, preferably 10% less than the protection power; similarly, when the drain-source voltage is greater than the first preset voltage and less than or equal to the second preset voltage, the maximum power of the power switch M1, that is, the maximum power of the oblique line segment of the curve 520 is more than 5% less than the protection power, preferably 10% less than the protection power; similarly, when the drain-source voltage is greater than the second preset voltage and less than or equal to the upper voltage limit value allowed by the specification, the product of the upper voltage limit value and the preset lower current limit is the maximum power, which is generally 5% or more less than the protection power, preferably 10% less than the protection power. By setting in this way, it is possible to prevent the power on the curve 520 from reaching or exceeding the protection power due to process technology and other reasons, thereby reducing the impact on the intelligent electronic switch 200.

[0094] In this embodiment, the current subtractor does not subtract the first current limiting signal from the second conversion current signal to obtain the difference, but rather realizes the power association by setting the first preset current signal, and then associating the third current conversion signal with the first preset current signal and the drain-source voltage, that is, the third current conversion signal can represent the power on the power switch M1, and by setting the third current limiting threshold to be less than or equal to the signal corresponding to the third current conversion signal ( Figure 6 Curve 520 in the figure) realizes that the real-time power on the power switch M1 is less than or equal to the product of the drain-source voltage and the signal corresponding to the third current conversion signal, and the product is smaller than the protection power, thereby ensuring that the real-time power on the power switch M1 is smaller than the protection power, and preventing the power switch M1 from being damaged due to heating.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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 reducing power, 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, which is connected to the current limiting end, and the current limiting generating module outputs a corresponding first current limiting signal based on the resistance value of the regulating resistor; a voltage regulating module, connected to the first end and the second end of the power switch to obtain a drain-source voltage, and further connected to the current limiting generating module, wherein the voltage regulating module outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal, wherein the second current limiting signal is smaller than a signal derived from the first current limiting signal, wherein the larger the drain-source voltage is, the smaller the second current limiting signal is; A current limiting control unit is connected to the voltage regulating 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 second current limiting signal.

2. The intelligent electronic switch according to claim 1, characterized in that: The voltage regulation module includes a voltage-current conversion module and an operation unit. The voltage-current conversion module is connected to the first end and the second end of the power switch to convert the drain-source voltage into a corresponding first conversion current signal. The operation unit is connected to the voltage-current conversion module and the current limiting generation module. The operation unit outputs the second current limiting signal based on the first conversion current signal and the first current limiting signal.

3. The intelligent electronic switch according to claim 2, characterized in that: The second current limiting signal is obtained by subtracting a signal derived from the first current limiting signal from a signal derived from the first conversion current signal.

4. The intelligent electronic switch according to claim 1, characterized in that: Within the voltage upper limit of the intelligent electronic switch, the power on the power switch is always smaller than the protection power.

5. The intelligent electronic switch according to claim 4, characterized in that: The voltage regulation module includes a voltage-current conversion module, a reference upper limit current generating unit, and an operation unit. The voltage-current conversion module is connected to the first end and the second end of the power switch to convert the drain-source voltage into a corresponding first conversion current signal. The reference upper limit current generating unit is used to generate a first preset current signal. The operation unit is connected to the voltage-current conversion module and the reference upper limit current generating unit. The operation unit operates the first preset current signal and a signal derived from the first conversion current signal to output a third conversion current signal, wherein the product of the drain-source voltage and the signal derived from the third conversion current signal is less than the protection power. When the signal derived from the first current limiting signal is greater than the signal derived from the third conversion current signal, the second current limiting signal corresponds to the third conversion current signal.

6. The intelligent electronic switch according to claim 5, characterized in that: The third conversion current signal is obtained through subtraction calculation.

7. The intelligent electronic switch according to claim 5, characterized in that: The voltage regulation module includes a power limit comparison unit, which is connected to the current limit generation module, the current limit control unit, and the operation unit. The power limit comparison unit includes a first current mirror and a second current mirror, wherein the first current mirror is connected to the current limit generation module and the current limit control unit, and the second current mirror is connected to the first current mirror and connected to the third conversion current signal; Among them, the first current mirror is used to mirror the current flowing through the current limiting generating module to obtain a first current corresponding signal, and the second current mirror mirrors the third conversion current signal to obtain a fourth conversion current signal. The first current corresponding signal and the fourth conversion current signal are located on the same current path. When the first current corresponding signal is greater than the fourth conversion current signal, the fourth conversion current signal is selected to correspond to the second current limiting signal.

8. The intelligent electronic switch according to claim 7, characterized in that: The first current mirror includes a ninth MOS tube and a tenth MOS tube, and the second current mirror includes a seventh MOS tube, an eighth MOS tube and an eleventh MOS tube; Wherein, the first end of the ninth MOS tube is connected to the current limiting generating module, the second end of the ninth MOS tube is connected to the first end of the eighth MOS tube, the control end of the ninth MOS tube is connected to the first end thereof, the control end of the tenth MOS tube is connected to the control end of the ninth MOS tube, the first end of the tenth MOS tube is used to output a second current limiting signal, and the second end of the tenth MOS tube is connected to the first end of the eleventh MOS tube; The control end of the eighth MOS tube is connected to the control end of the seventh MOS tube, the first end of the seventh MOS tube is connected to its control end, the first end of the seventh MOS tube is also connected to the third conversion current signal, the control end of the eleventh MOS tube is connected to the control end of the eighth MOS tube, and the second end of the seventh MOS tube, the second end of the eighth MOS tube, and the second end of the eleventh MOS tube are all connected to the power ground terminal.

9. The intelligent electronic switch according to any one of claims 1 to 8, characterized in that: When the drain-source voltage is greater than the first preset voltage and less than the second preset voltage, the voltage regulating module outputs a second current limiting signal based on the drain-source voltage and the first current limiting signal, and the more the drain-source voltage is greater than the first preset voltage, the smaller the second current limiting signal or the maximum value of the second current limiting signal.

10. An integrated circuit chip, characterized in that: It includes the intelligent electronic switch as claimed in any one of claims 1 to 9, 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.

11. A chip product, characterized in that: The intelligent electronic switch according to any one of claims 1 to 9, 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.

12. An electromechanical device, characterized in that: The intelligent electronic switch according to any one of claims 1 to 9, the integrated circuit chip according to claim 10, or the chip product according to claim 11; 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.

13. The electromechanical device according to claim 12, characterized in that The electromechanical device includes an automobile.

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