Intelligent electronic switch for anomaly detection, chip, chip product and automobile

Abstract

The invention provides an intelligent electronic switch for anomaly detection, a chip, a chip product and an automobile, in the intelligent electronic switch, a control circuit is used for controlling a power switch to be turned on or turned off, a drain-source voltage value of the power switch is obtained through a clamping circuit, and an adjustment signal is output according to the drain-source voltage value and an accessed reference voltage value; the clamping circuit is used for clamping a drain-source voltage value to a reference voltage value, so that the control circuit adjusts a grid control signal output to the power switch to clamp the drain-source voltage value to the reference voltage value, and in addition, the clamping circuit is also used for collecting a deviation voltage between the drain-source voltage value and the reference voltage value, and outputting an abnormal signal when the deviation voltage is greater than a preset voltage threshold value to indicate that the load is abnormal. The invention provides a load abnormity detection scheme, which can realize the purpose of detecting whether the load is abnormal or not under the condition that the drain-source voltage value of the clamping power switch is constant by means of the clamping function of the clamping circuit.

Description

Technical Field

[0001] The present application relates to the field of electronic circuit technology, and in particular to an intelligent electronic switch, chip, chip product and automobile for abnormality detection. Background Art

[0002] An intelligent electronic switch is an electronic component that controls the on / off of a load circuit. It integrates a variety of protection functions and diagnostic functions to improve the reliability of the intelligent electronic switch. The intelligent electronic switch has a power switch inside. By controlling the power switch to turn on or off, it can control whether the power supply is supplied to the load.

[0003] At present, load short circuit and load open circuit are two forms of load abnormality. Load short circuit and load open circuit and other abnormality detection are essential functions of intelligent electronic switches. When the intelligent electronic switch detects abnormalities such as load short circuit or open circuit, it will turn off the power switch in time to protect the power switch from being damaged. There are many solutions for detecting abnormalities such as load short circuit and open circuit in the prior art. This application proposes a new abnormality detection method. Summary of the invention

[0004] The present application provides an intelligent electronic switch, a chip, a chip product and a car for abnormality detection, which are used to perform load abnormality detection when the drain-source voltage value of a clamped power switch is constant.

[0005] In a first aspect, the present application provides an intelligent electronic switch for abnormality detection, comprising a power supply terminal, a power ground terminal, a load output terminal, a power switch, a control circuit, and a clamping circuit;

[0006] The power supply end and the power ground end are used to be connected to a battery, the power switch is used to be connected in series with a load, a first end thereof is connected to the power supply end or the power ground end, a second end thereof is connected to the load output end, and a control end thereof is connected to the control circuit, and the control circuit is used to control the power switch to be turned on or off;

[0007] The clamping circuit is connected to the source and drain of the power switch, and is used to obtain the drain-source voltage value of the power switch, and output an adjustment signal according to the drain-source voltage value and the connected reference voltage value, so that the control circuit adjusts the gate control signal output to the power switch to clamp the drain-source voltage value to the reference voltage value, and the gate control signal is positively correlated with the load current flowing through the power switch;

[0008] The clamp circuit is also used to collect a deviation voltage value between the drain-source voltage value and the reference voltage value, and output an abnormal signal when the deviation voltage value is greater than a preset voltage threshold, wherein the abnormal signal is used to indicate a load abnormality.

[0009] Optionally, the clamping circuit includes a drain-source voltage detection unit, an operation processing unit, a signal processing unit and an abnormality judgment unit;

[0010] The input end of the drain-source voltage detection unit is respectively connected to the drain and source of the power switch, and the output end thereof is connected to the operation processing unit. The operation processing unit is also used to access the reference voltage value. The operation processing unit is connected to the signal processing unit and the abnormality judgment unit;

[0011] The drain-source voltage detection unit is used to obtain the drain voltage value and the source voltage value of the power switch and output the drain-source voltage value, the operation processing unit compares the drain-source voltage value with the reference voltage value and outputs a deviation voltage, the signal processing unit generates the adjustment signal based on the deviation voltage, and the abnormality judgment unit compares the deviation voltage with a preset voltage threshold and outputs an abnormality signal when the deviation voltage is greater than the preset voltage threshold.

[0012] Optionally, the operation processing unit is also used to output the deviation current corresponding to the deviation voltage according to the drain-source voltage value and the reference voltage value, the signal processing unit generates the adjustment signal based on the deviation current, and the abnormality judgment unit compares the deviation current with a preset current threshold and outputs an abnormal signal when the deviation current is greater than the preset current threshold.

[0013] Wherein, the operation processing unit includes a voltage-current conversion module, a first operation module and a second operation module, and the deviation current includes a positive deviation current and a negative deviation current;

[0014] The voltage-current conversion module has one input end connected to the drain-source voltage detection unit, another input end thereof is used to access the reference voltage value, and an output end thereof is respectively connected to the first operation module and the second operation module, and the first operation module and the second operation module are respectively connected to the signal processing unit and the abnormality judgment unit;

[0015] The voltage-current conversion module is used to convert the drain-source voltage value into a first current value, and convert the reference voltage value into a reference current value, and output both to the first operation module and the second operation module;

[0016] When the drain-source voltage value is greater than the reference voltage value, the first current value is less than the reference current value, the first operation module outputs a positive deviation current, and the second operation module has no output; when the drain-source voltage value is less than the reference voltage value, the first current value is greater than the reference current value, the first operation module has no output, and the second operation module outputs a negative deviation current.

[0017] Among them, the signal processing unit outputs a first adjustment signal when it detects that the first operation module outputs a positive deviation current to instruct the control circuit to increase the output gate control signal, and outputs a second adjustment signal when it detects that the second operation module outputs a negative deviation current to instruct the control circuit to decrease the output gate control signal.

[0018] The abnormality judgment unit includes a first abnormality judgment module and a second abnormality judgment module, the first abnormality judgment module is connected to the first operation module, and the second abnormality judgment module is connected to the second operation module;

[0019] When the first abnormality judgment module detects that the first operation module outputs the positive deviation current, the first abnormality judgment module compares the positive deviation current with a first reference current value, and outputs a short-circuit signal if the positive deviation current is greater than the first reference current value;

[0020] When the second abnormality judgment module detects that the second operation module outputs the negative deviation current, the second abnormality judgment module compares the negative deviation current with a second reference current value, and outputs an open circuit signal if the negative deviation current is greater than the second reference current value;

[0021] Wherein, the preset current threshold includes the first reference current value and the second reference current value.

[0022] Optionally, the intelligent electronic switch further includes an input terminal and a first timing circuit;

[0023] The input end is connected to the control circuit and the first timing circuit respectively, and the first timing circuit is connected to the clamping circuit;

[0024] When the input terminal receives a start control signal, the control circuit controls the power switch to turn on, and at the same time, the first timing circuit starts timing;

[0025] The first timing circuit outputs a timing arrival signal when the continuous timing duration reaches a first preset duration, so that the clamping circuit starts to work.

[0026] Optionally, the intelligent electronic switch further includes an input terminal and a gate-source voltage detection circuit;

[0027] The input end is connected to the control circuit and the gate-source voltage detection circuit respectively, and the gate-source voltage detection circuit is connected to the clamping circuit;

[0028] When the input end receives a start control signal, the control circuit controls the power switch to start conducting. At the same time, the gate-source voltage detection circuit obtains the gate voltage value and the source voltage value of the power switch and obtains the gate-source voltage value, and outputs an enable signal when the gate-source voltage value is greater than or equal to the gate-source reference voltage value, so that the clamping circuit starts working.

[0029] Optionally, the intelligent electronic switch also includes a reference voltage setting pin and a reference voltage setting unit, the reference voltage setting unit is connected to the clamping circuit and the reference voltage setting pin, the reference voltage setting pin is also used to connect to a first resistor, the first resistor is used to set the reference voltage value based on the reference voltage setting unit, the larger the resistance of the first resistor, the larger the reference voltage value.

[0030] Optionally, when the power switch operates in the saturation region and the drain-source voltage value of the power switch is clamped to the reference voltage value, the greater the load current flowing through the power switch, the greater the gate control signal, and the smaller the internal resistance value of the power switch.

[0031] In a second aspect, an embodiment of the present application provides an integrated circuit chip, comprising an intelligent electronic switch for abnormality detection as described in the first aspect, wherein the power supply end is a power supply pin, the power ground end is a power ground pin, and the load output end is a load output pin.

[0032] In a third aspect, an embodiment of the present application provides a chip product, comprising the intelligent electronic switch for abnormality detection as described in the first aspect, wherein components of the intelligent electronic switch other than the power switch are located on a first integrated circuit chip, and the power switch is located on a second integrated circuit chip;

[0033] Among them, the power supply end is a power supply pin, the power ground end is a power ground pin, and the load output end is a load output pin. The power supply pin and the power ground pin are located on a first integrated circuit chip, and the load output pin is located on a second integrated circuit chip.

[0034] In a fourth aspect, an embodiment of the present application provides an automobile, comprising the intelligent electronic switch for abnormality detection as described in the first aspect, or the integrated circuit chip as described in the second aspect, or the chip product as described in the third aspect;

[0035] It also includes a battery, a load and a microcontroller, wherein the positive electrode of the battery is connected to the power supply terminal, the negative electrode of the battery 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, and the microcontroller is connected to the intelligent electronic switch.

[0036] The present application provides an intelligent electronic switch, chip, chip product and automobile for abnormality detection. In the intelligent electronic switch, the control circuit is used to control the power switch to turn on or off, and the drain-source voltage value of the power switch is obtained through the clamping circuit, and an adjustment signal is output according to the drain-source voltage value and the reference voltage value connected, so that the control circuit adjusts the gate control signal output to the power switch to clamp the drain-source voltage value to the reference voltage value. In addition, the clamping circuit is also used to collect the deviation voltage between the drain-source voltage value and the reference voltage value, and output an abnormal signal when the deviation voltage is greater than a preset voltage threshold to indicate that the load is abnormal. That is, the present application provides a load abnormality detection scheme, which can achieve the purpose of detecting whether the load is abnormal when the drain-source voltage value of the clamped power switch is constant by means of the clamping function of the clamping circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0038] Figure 1 It is a circuit module schematic diagram of the intelligent electronic switch and its peripheral components provided in the first embodiment of the present application;

[0039] Figure 2 It is a schematic diagram of the working curve of the power switch (MOS tube);

[0040] Figure 3 Yes Figure 1 A schematic diagram of a circuit module after the clamping circuit in the circuit module is implemented;

[0041] Figure 4 Yes Figure 3 A schematic diagram of a circuit module after the operation processing unit, the signal processing unit and the abnormality judgment unit in the circuit module are completed;

[0042] Figure 5 It is a circuit module schematic diagram of an intelligent electronic switch and its peripheral components provided in the second embodiment of the present application;

[0043] Figure 6 It is a circuit module schematic diagram of an intelligent electronic switch and its peripheral components provided in the third embodiment of the present application;

[0044] Figure 7It is a circuit module schematic diagram of an intelligent electronic switch and its peripheral components provided in the fourth embodiment of the present application.

[0045] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are 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.

[0047] 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 comprising a series of steps or modules is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0048] In addition, the terms "first", "second" and "third" are used to distinguish different objects, rather than to describe a specific order. The electrical connection of the present application includes direct electrical connection and indirect electrical connection. Indirect electrical connection means that other electronic components, pins, etc. may exist between the two electrically connected components. The XX end mentioned in the present application may be an actual terminal, or it may not be an actual terminal, for example, it is only one end of a component or one end of a wire. The "and / or" mentioned in the present application includes three situations. For example, A and / or B includes three situations: A, B, A and B.

[0049] With the acceleration of the transformation of the automotive intelligent industry, more and more electronic switches are installed in cars. In practical applications, intelligent electronic switches are used to drive and switch the loads in the car, and protect and diagnose the loads because of their high reliability, flexibility, low power consumption, small size and light weight. They are widely used in automotive electronics, industrial automation, medical equipment and other fields. Therefore, intelligent electronic switches have gradually become the trend of switch development.

[0050] Smart electronic switches are usually used to couple loads with batteries. They are electronic components that control the on and off of load circuits. They have one or more diagnostic capabilities and protection features, such as protection against over-temperature, overload, short-circuit events, and open-circuit events. For example, a smart electronic switch has a power switch. When the smart electronic switch is over-temperature, overloaded, short-circuited, or open-circuited, the power switch will be turned off, disconnecting the path between the battery and the load, thereby protecting the power switch and the load from damage and improving the reliability of the smart electronic switch during use.

[0051] It is understandable that in actual applications, the load types of intelligent electronic switches are diverse (for example, inductors, capacitors, resistors, or a combination of the three) and the working environment is harsh, so the application end will have particularly high requirements for its reliability. Among them, abnormal detection of intelligent electronic switches is a relatively important item in reliability requirements. For example, when the load connected to the power switch is short-circuited and the power switch is turned on, there will be uncontrollable current from the battery through the power switch to the ground. At this time, the instantaneous short-circuit power on the power switch may be too large due to the excessive current flowing through the power switch, which may cause the power switch to burn out; and when the load connected to the power switch is open-circuited, even if the power switch is turned on, there is almost no current flowing through the power switch, making the circuit using the intelligent electronic switch unable to work normally.

[0052] In response to the above technical problems, the industry has developed a variety of abnormality detection solutions for open or short-circuited loads, for example, by detecting the output voltage of a power switch or detecting the magnitude of the current flowing through the power switch, etc. to detect whether the load is abnormal. The embodiment of the present application provides an abnormality detection method that is different from the prior art, which can perform load abnormality detection based on applications such as controlling the voltage drop of the power switch to be constant.

[0053] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0054] Figure 1 1 is a schematic diagram of a circuit module of an intelligent electronic switch and its peripheral components provided in the first embodiment of the present application. In this embodiment, the intelligent electronic switch can be used for abnormality detection, specifically, Figure 1 As shown, the intelligent electronic switch 20 includes a power supply terminal VBAT, a power ground terminal GND, a load output terminal OUT, a power switch Q, a control circuit 21 and a clamping circuit 22 .

[0055] Among them, the power supply terminal VBAT and the power ground terminal GND are used to connect to the battery 10. Specifically, the power supply terminal VBAT is connected to the positive electrode of the battery 10, and the power ground terminal GND is connected to the negative electrode of the battery 10. The power switch Q is used to be connected in series with the load RL, and its first end is connected to the power supply terminal VBAT or the power ground terminal GND, and its second end is connected to the load output terminal OUT. Its control end is connected to the control circuit 21, and the control circuit 21 is used to control the power switch Q to turn on or off.

[0056] For example, in Figure 1 In the illustrated embodiment, the first end of the power switch Q is connected to the power supply terminal VBAT. At this time, the power switch Q is connected as a high-side switch (high-side switch), which is actually a switch connected between the positive electrode of the battery 10 and the load RL. In other embodiments of the present application, the first end of the power switch Q is connected to the power ground terminal GND, that is, the power switch Q is connected between the negative electrode of the battery 10 and the load RL. At this time, the power switch Q is connected as a low-side switch (low-side switch), which will not be described in detail here.

[0057] Continue to refer to Figure 1 As shown, the clamping circuit 22 is connected to the source s and the drain d of the power switch Q, and is used to obtain the drain-source voltage value Vds of the power switch Q, and output the adjustment signal Vadj according to the drain-source voltage value Vds and the connected reference voltage value Vref, so that the control circuit 21 adjusts the gate control signal Vg output to the power switch Q, so as to clamp the drain-source voltage value Vds to the reference voltage value Vref, and the gate control signal Vg is positively correlated with the load current Ids flowing through the power switch Q.

[0058] In this embodiment, the control circuit 21 can control the state of the power switch Q based on the received switch control signal (ON / OFF signal). For example, the control circuit 21 controls the power switch Q to turn on and conduct when receiving the start control signal (ON signal), and controls the power switch Q to work in the saturation region (i.e., constant current region) after the power switch Q is turned on, so that under the action of the reference voltage value Vref, the clamp circuit 22, the control circuit 21, and the power switch Q can be connected to form a negative feedback loop; the clamp circuit 22 can compare the drain-source voltage value Vds with the reference voltage value Vref and generate an adjustment signal Vadj according to the difference between the two, so that the control circuit 21 adjusts the gate control signal Vg output to the power switch Q to control the on-resistance of the power switch Q. That is, in this embodiment, when the resistance of the load RL changes, that is, when the load current Ids flowing through the power switch Q changes, by adjusting the gate control signal Vg output to the power switch Q, and then adjusting the on-resistance of the power switch Q, it is possible to ensure that the drain-source voltage value Vds of the power switch Q remains substantially unchanged, thereby achieving the purpose of a constant voltage drop of the power switch Q.

[0059] For example, Figure 2 This is a schematic diagram of the working curve of the power switch (MOS tube). Figure 2 As shown, the working area of ​​the MOS tube includes a cut-off region, a linear region, and a saturation region. When Vgs<Vgs(th), the power switch is in the cut-off region and is not turned on at this time. When Vgs>Vgs(th), if Vds is less than the value corresponding to the pre-pinch-off trajectory, the power switch works in the linear region, and if Vds is greater than the value corresponding to the pre-pinch-off trajectory, the power switch works in the saturation region. Among them, when the power switch Q works in the saturation region, if the drain-source voltage value Vds is kept unchanged, the gate-source voltage value Vgs of the power switch Q is positively correlated with the current value (i.e., the load current Ids) flowing through the power switch Q, that is, if the current value flowing through the power switch Q is larger, the gate control signal Vg is larger, that is, the gate-source voltage value Vgs is larger, and if the current value flowing through the power switch Q is smaller, the gate control signal Vg is smaller, and the gate-source voltage value Vgs is smaller.

[0060] In an embodiment of the present application, after the negative feedback loop is stabilized, as an example, if the load current Ids flowing through the power switch Q decreases, at this time, the clamping circuit 22 will detect that the drain-source voltage value Vds is less than the reference voltage value Vref. According to the working characteristics of the power switch Q in the saturation region, the clamping circuit 22 outputs the adjustment signal Vadj to make the control circuit 21 reduce the gate control signal Vg output to the power switch Q, so that the internal resistance value Ron of the power switch Q can be increased to prevent the drain-source voltage value Vds of the power switch Q from decreasing. The one decreases and the one increases, so that the product of the internal resistance value Ron of the power switch Q and the load current Ids flowing through the power switch Q always follows the reference voltage value Vref, so as to achieve the purpose of clamping the drain-source voltage value Vds of the power switch Q to the reference voltage value Vref. As another example, if the load current Ids flowing through the power switch Q increases, at this time, the clamping circuit 22 will detect that the drain-source voltage value Vds is greater than the reference voltage value Vref. The clamping circuit 22 outputs the adjustment signal Vadj to enable the control circuit 21 to increase the gate control signal Vg output to the power switch Q, so that the internal resistance value Ron of the power switch Q can be reduced to prevent the drain-source voltage value Vds of the power switch Q from increasing. The increase and decrease can make the product of the internal resistance value Ron of the power switch Q and the load current Ids flowing through the power switch Q always follow the reference voltage value Vref, thereby achieving the purpose of clamping the drain-source voltage value Vds of the power switch Q to the reference voltage value Vref.

[0061] It can be understood that in the present embodiment, the gate control signal Vg outputted by the control circuit 21 to the control terminal of the power switch Q is positively correlated with the load current Ids flowing through the power switch Q, that is, when the load current Ids increases, the internal resistance value Ron of the power switch Q can be reduced by increasing the gate control signal Vg, thereby clamping the drain-source voltage value Vds of the power switch Q to the reference voltage value Vref; similarly, when the load current Ids decreases, the internal resistance value Ron of the power switch Q can be increased by decreasing the gate control signal Vg, and the drain-source voltage value Vds of the power switch Q can also be clamped to the reference voltage value Vref.

[0062] From the above analysis, it can be seen that in the embodiment of the present application, when the power switch Q operates in the saturation region and the drain-source voltage value Vds of the power switch Q is clamped to the reference voltage value Vref, the larger the load current Ids flowing through the power switch Q, the larger the gate control signal Vg, and the smaller the internal resistance value Ron of the power switch Q, that is, within the adjustable range of the gate control signal Vg, the gate control signal Vg is positively correlated with the load current Ids flowing through the power switch Q and negatively correlated with the internal resistance value Ron of the power switch Q.

[0063] Optionally, when an abnormality occurs in the load RL connected to the power switch Q, for example, when the load RL is short-circuited or the load RL is open-circuited, the negative feedback loop composed of the clamp circuit 22, the control circuit 21 and the power switch Q may be out of the stable state, and the drain-source voltage value Vds of the power switch Q will not be able to follow the reference voltage value Vref. For example, when the load RL is short-circuited, the load current Ids flowing through the power switch Q will suddenly become very large, and accordingly, the drain-source voltage value Vds of the power switch Q will also become very large, so large that it exceeds the maximum adjustment limit of the internal resistance value of the power switch Q, that is, when the internal resistance value of the power switch is adjusted to the minimum, the drain-source voltage value Vds of the power switch Q cannot be pulled down to the reference voltage value Vref, and at this time, the negative feedback loop will be out of the stable state. Similarly, when the load RL is open-circuited, the load current Ids flowing through the power switch Q will suddenly become very small, and accordingly, the drain-source voltage value Vds of the power switch Q will become very small, so small that when the gate control signal output by the control circuit 21 has reached the maximum value, it is still unable to pull the drain-source voltage value Vds of the power switch Q up to the reference voltage value Vref, thereby causing the negative feedback loop to deviate from the stable state.

[0064] Optionally, inside the clamp circuit 22, when the deviation voltage between the drain-source voltage value Vds of the power switch Q and the reference voltage value Vref is small, the clamp circuit 22 can dynamically adjust the output of the clamp circuit 22 according to the deviation voltage through an internal adjustment mechanism. However, when the deviation voltage between the drain-source voltage value Vds of the power switch Q and the reference voltage value Vref is large, for example, when the deviation voltage is greater than a preset voltage threshold, the dynamic adjustment mechanism inside the clamp circuit 22 will be unbalanced. By improving the clamp circuit 22, it can be determined whether the dynamic adjustment mechanism inside the clamp circuit 22 is unbalanced, and then it can be determined whether the load RL is abnormal.

[0065] Continue to refer to Figure 1 As shown, in this embodiment, the clamp circuit 22 is also used to collect the deviation voltage between the drain-source voltage value Vds and the reference voltage value Vref, and output an abnormal signal when the deviation voltage is greater than a preset voltage threshold, and the abnormal signal is used to indicate that the load RL is abnormal. The preset voltage threshold is related to the reference voltage value Vref, the maximum Vds value when the power switch is working normally, and the minimum Vds value, which will not be described here.

[0066] Optionally, in this embodiment, the clamping circuit 22 can start working after the power switch Q is turned on, so that the negative feedback loop composed of the clamping circuit 22, the control circuit 21 and the power switch Q automatically enters the clamping state, and at the same time enters the detection state of whether the load RL is abnormal.

[0067] As an example, when the load RL is short-circuited, the load current Ids flowing through the power switch Q becomes very large, and accordingly, the drain-source voltage value Vds of the power switch Q also becomes very large, causing the deviation voltage between the drain-source voltage value Vds and the reference voltage value Vref to be large enough to exceed the preset voltage threshold, and at this time, it can be considered that the load RL has a short-circuit abnormality. Similarly, when the load RL is open-circuited, the load current Ids flowing through the power switch Q will suddenly become very small, and accordingly, the drain-source voltage value Vds of the power switch Q will also become very small, which will also cause the deviation voltage between the drain-source voltage value Vds and the reference voltage value Vref (at this time, the reference voltage value Vref is greater than the drain-source voltage value Vds) to be large enough to exceed the preset voltage threshold, and at this time, it can be considered that the load RL has an open-circuit abnormality.

[0068] Optionally, the clamp circuit 22 may also collect a deviation current corresponding to a deviation voltage between the drain-source voltage value Vds and the reference voltage value Vref, and output an abnormal signal when the deviation current is greater than a preset current threshold.

[0069] Exemplarily, in this embodiment, the clamp circuit 22 has a voltage-to-current conversion function and a current processing function. Therefore, the clamp circuit 22 can convert the acquired drain-source voltage value Vds into a conversion current and the reference voltage value Vref into a reference current value, and then determine whether the deviation current between the two exceeds a preset current threshold, and then determine whether the load RL is abnormal.

[0070] As an example, when the load RL is short-circuited, the load current Ids flowing through the power switch Q becomes very large, and accordingly, the drain-source voltage value Vds of the power switch Q also becomes very large, resulting in the conversion current corresponding to the drain-source voltage value Vds being greater than the reference current value corresponding to the reference voltage value Vref. When the deviation current between the conversion current and the reference current value is so large as to exceed the preset current threshold, it is considered that the load RL is abnormal. Similarly, when the load RL is open-circuited, the load current Ids flowing through the power switch Q will suddenly become very small, and accordingly, the drain-source voltage value Vds of the power switch Q will also become very small, which results in the conversion current corresponding to the drain-source voltage value Vds being less than the reference current value corresponding to the reference voltage value Vref. When the deviation current between the reference current value and the conversion current is so large as to exceed the preset current threshold, it is also considered that the load RL is abnormal.

[0071] It can be understood that when the load RL is short-circuited and when the load RL is open-circuited, the direction of the deviation current is different. In the two cases, the preset current threshold can also be different values, which can be determined according to actual needs and the size of the reference voltage value Vref, and will not be elaborated in this embodiment.

[0072] Optional, see Figure 1 As shown, when the clamp circuit 22 determines that the load RL is abnormal, the abnormal signal output by the clamp circuit 22 can be received by the control circuit 21. When receiving the abnormal signal, the control circuit 21 can directly control the power switch Q to be turned off, or perform other protection measures, which are not limited in this embodiment.

[0073] Optionally, in this embodiment, the power switch Q can be an N-type metal-oxide-semiconductor field-effect transistor (N Metal-Oxide-Semiconductor Field-Effect Transistor, NMOS FET, referred to as NMOS tube), a PMOS tube, a junction field effect transistor (Junction Field Effect Transistor, referred to as JFET) or an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, referred to as IGBT), etc., and the N-type MOS tube is used as an example for illustration in the figure. In other embodiments of the present application, the power switch Q can also 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), etc. The embodiment of the present application does not limit the form of expression of the power switch Q. In addition, when the power switch Q is an NMOS tube or a PMOS tube, the above-mentioned adjustment signal Vadj and the gate control signal Vg are voltage signals. When the negative feedback loop of the present application is stable, when the control circuit 21 outputs the gate control signal Vg based on the adjustment signal Vadj to control the power switch Q, the power switch Q operates in the saturation region.

[0074] Optionally, a fuse (not shown) may be connected in series between the battery 10 and the power supply terminal VBAT to prevent a fault caused by excessive current in the line. Other components may be provided between the power ground terminal GND and the negative electrode of the battery 10, for example, a reverse connection prevention diode and a current limiting resistor connected in parallel to improve the stability of the intelligent electronic switch.

[0075] Optional, in Figure 1 In the schematic diagram shown, the connection relationship between the clamping circuit 22, the control circuit 21, etc. and the power supply unit is not shown, but in actual application, a power supply unit can be set inside the intelligent electronic switch 20, and the internal power supply unit is connected to the power supply terminal VBAT to step down the voltage of the power supply terminal VBAT and provide it to the clamping circuit 22, the control circuit 21 and other circuits. In other embodiments, the power supply unit may not be set inside the intelligent electronic switch 20. In this case, a step-down unit needs to be set between the power supply terminal VBAT and the positive electrode of the battery 10 to step down the voltage input to the power supply terminal VBAT to the rated working voltage of the intelligent electronic switch 20, so that the voltage at the power supply terminal VBAT can directly power the circuit inside the intelligent electronic switch 20.

[0076] The intelligent electronic switch for abnormality detection provided in the embodiment of the present application, in the application scenario of controlling the voltage drop of the power switch Q to be constant, when the load RL has an abnormality such as a short circuit or an open circuit, the negative feedback loop composed of the clamping circuit, the control circuit and the power switch Q will deviate from the stable state, that is, the clamping circuit can output an abnormal signal based on the deviation voltage of the drain-source voltage value and the reference voltage value Vref, thereby achieving the purpose of load abnormality detection.

[0077] To achieve anomaly detection, the following Figure 1 Based on the embodiment shown, combined Figure 3 , Figure 4 The abnormality detection principle of the clamp circuit 22 is explained. Figure 3 Yes Figure 1 Schematic diagram of the circuit module after the clamping circuit in the circuit module. Figure 4 Yes Figure 3 A schematic diagram of a circuit module after the operation processing unit, signal processing unit and abnormality judgment unit in the circuit module are completed. Figure 3 In the schematic diagram shown, the clamping circuit 22 includes a drain-source voltage detection unit 221 , an operation processing unit 222 , a signal processing unit 223 and an abnormality determination unit 224 .

[0078] Continue to refer to Figure 3 As shown, the input end of the drain-source voltage detection unit 221 is respectively connected to the drain d and the source s of the power switch Q, and the output end is connected to the operation processing unit 222. The operation processing unit 222 is also used to access the reference voltage value Vref. The operation processing unit 222 is connected to the signal processing unit 223 and the abnormality judgment unit 224.

[0079] In this embodiment, the drain-source voltage detection unit 221 is used to obtain the drain voltage value Vd and the source voltage value Vs of the power switch Q and output the drain-source voltage value Vds. The operation processing unit 222 compares the drain-source voltage value Vds with the reference voltage value Vref and outputs a deviation voltage. The signal processing unit 223 generates an adjustment signal Vadj based on the deviation voltage. The abnormality judgment unit 224 compares the deviation voltage with a preset voltage threshold and outputs an abnormal signal when the deviation voltage is greater than the preset voltage threshold.

[0080] Exemplarily, in this embodiment, when the drain-source voltage detection unit 221 is implemented by the differential amplifier unit DA1, it can collect the drain voltage value Vd and the source voltage value Vs of the power switch Q through two input terminals during operation and output the drain-source voltage value Vds after performing differential processing (such as subtraction operation).

[0081] The operation processing unit 222 has at least two input terminals, one terminal is used to receive the drain-source voltage value Vds, and the other input terminal is used to receive the reference voltage value Vref, so that the operation processing unit 222 can compare the drain-source voltage value Vds with the reference voltage value Vref, and express the comparison result between the two by means of deviation voltage value and deviation direction.

[0082] Exemplarily, the operation processing unit 222 is also used to output a deviation current corresponding to the deviation voltage according to the drain-source voltage value Vds and the reference voltage value Vref, the signal processing unit 223 generates an adjustment signal Vadj based on the deviation current, and the abnormality judgment unit 224 compares the deviation current with a preset current threshold and outputs an abnormal signal when the deviation current is greater than the preset current threshold.

[0083] For example, in the embodiments of this application, please refer to Figure 4 As shown, the operation processing unit 222 may include a voltage-current conversion module 222A, a first operation module 222B and a second operation module 222C, and correspondingly, the deviation current includes a positive deviation current I2 and a negative deviation current I3. Among them, the voltage-current conversion module 222A has one input end connected to the drain-source voltage detection unit 221, and another input end thereof is used to access the reference voltage value Vref, and its output end is respectively connected to the first operation module 222B and the second operation module 222C, and the first operation module 222B and the second operation module 222C are respectively connected to the signal processing unit 223 and the abnormality judgment unit 224.

[0084] In this embodiment, the voltage-current conversion module 222A is used to convert the drain-source voltage value Vds into the first current value I1, convert the reference voltage value Vref into the reference current value Iref, and output them to the first operation module 222B and the second operation module 222C respectively. As an example, when the drain-source voltage value Vds is greater than the reference voltage value Vref, the first current value I1 is less than the reference current value Iref, the first operation module 222B outputs a positive deviation current I2, and the second operation module 222C has no output; as another example, when the drain-source voltage value Vds is less than the reference voltage value Vref, the first current value I1 is greater than the reference current value Iref, the first operation module 222B has no output, and the second operation module 222C outputs a negative deviation current I3.

[0085] In a specific implementation, referring to Figure 4As shown, the voltage-current conversion module 222A may include a constant current source I00, a first PMOS tube P11, a first NMOS tube N11, a first second NMOS tube N12, a first second PMOS tube P12, a second PMOS tube P21 and a second NMOS tube N21, the first operation module 222B includes a first third PMOS tube P13 and a second second NMOS tube N22, and the second operation module 222C includes a first fourth PMOS tube P14 and a second third NMOS tube N23.

[0086] Among them, the first PMOS transistor P11 and the second PMOS transistor P21 are input pair transistors of the operational amplifier, and the sources of both are connected to the output end of the constant current source I00. The gate of the first PMOS transistor P11 is used to access the reference voltage value Vref, and the gate of the second PMOS transistor P21 is connected to the drain-source voltage detection unit 221, that is, used to access the reference voltage value Vref. The first NMOS transistor N11 and the second NMOS transistor N21 are load transistors, and the sources of both are connected to the power ground terminal GND. The drain of the first NMOS transistor N11 is connected to the drain of the first PMOS transistor P11, and the drain of the second NMOS transistor N21 is connected to the drain of the second PMOS transistor P21.

[0087] In the present embodiment, the first-second NMOS transistor N12 is a mirror image transistor of the first-first NMOS transistor N11, and the first-second NMOS transistor N12 and the first-first NMOS transistor N11 form a first mirror image pair, the gate of the first-first NMOS transistor N11 is connected to its drain and the gate of the first-second NMOS transistor N12, the source of the first-second NMOS transistor N12 is connected to the power ground terminal GND, and the drain is connected to the drain of the first-second PMOS transistor P12, the gate of the first-second PMOS transistor P12 is connected to its drain and the gate of the first-third PMOS transistor P13 in the first operation module 222B, and the source is connected to the internal power supply terminal VDD, and the first-second PMOS transistor P12 and the first-third PMOS transistor P13 form a second mirror image pair.

[0088] The second-second NMOS tube N22 in the first operation module 222B is a mirror tube of the second-first NMOS tube N21, and the second-second NMOS tube N22 and the second-first NMOS tube N21 form a third mirror pair. The gate of the second-first NMOS tube N21 is connected to its drain and the gate of the second-second NMOS tube N22, the source of the second-second NMOS tube N22 is connected to the power ground terminal GND, and its drain is connected to the drain of the second-second NMOS tube N22, and the connection point between the drain of the second-second NMOS tube N22 and the drain of the first-third PMOS tube P13 is the output point of the second operation unit, which is respectively connected to the signal processing unit 223 and the abnormality judgment unit 224.

[0089] Continue to refer to Figure 4As shown, the gate of the first second PMOS transistor P12 is also connected to the gate of the first fourth PMOS transistor P14 in the second operation module 222C, and the two form a fourth mirror pair. The gate of the second first NMOS transistor N21 is also connected to the gate of the second third NMOS transistor N23 in the second operation module 222C, and the two form a fifth mirror pair. The drain of the first fourth PMOS transistor P14 is connected to the drain of the second third NMOS transistor N23, and the connection point between the two is the output point of the first operation unit, which is respectively connected to the signal processing unit 223 and the abnormality judgment unit 224.

[0090] For example, in this embodiment, the mirror ratio of the first mirror pair to the fifth mirror pair is 1:1 for explanation. In practical applications, it can be set according to actual needs, but it is necessary to ensure that the processing multiples of the first current value corresponding to the reference current value and the drain-source voltage value Vds compared in the first operation module 222B and the second operation module 222C are consistent.

[0091] Optionally, assuming that the reference voltage value Vref is 20mv, as an example, if the drain-source voltage value Vds of the power switch Q is 22mv, which is greater than the reference voltage value Vref, at this time, after the voltage-current conversion processing of the voltage-current conversion module 222A, the first current value I1 corresponding to the drain-source voltage value Vds is less than the reference current value Iref corresponding to the reference voltage value Vref, at this time, the second operation module 222C has no output, and the first operation module 222B has a current overflow, that is, it outputs a positive deviation current I2, and the greater the drain-source voltage value Vds is than the reference voltage value Vref, the greater the positive deviation current I2. The larger I2 is; as another example, if the drain-source voltage value Vds of the power switch Q is 18mv, which is less than the reference voltage value Vref, at this time, after the voltage-current conversion processing of the voltage-current conversion module 222A, the first current value I1 corresponding to the drain-source voltage value Vds is greater than the reference current value Iref corresponding to the reference voltage value Vref. At this time, the first operation module 222B has no output, and the second operation module 222C needs current supplement, that is, the second operation module 222C outputs a negative deviation current I3, and the smaller the drain-source voltage value Vds is than the reference voltage value Vref, the larger the negative deviation current I3 is.

[0092] It can be understood that in this embodiment, the signal processing unit 223 can collect the magnitude and direction of the deviation current and output the adjustment signal Vadj. That is, when the signal processing unit 223 detects the positive deviation current I2 output by the first operation module 222B, it outputs the first adjustment signal to instruct the control circuit 21 to increase the output gate control signal, and when the signal processing unit 223 detects the negative deviation current I3 output by the second operation module 222C, it outputs the second adjustment signal to instruct the control circuit 21 to decrease the output gate control signal.

[0093] Optionally, the adjustment signal Vadj may be a voltage deviation signal or an amplified signal of the voltage deviation signal after voltage acquisition of the deviation current, and the adjustment trend of the adjustment signal Vadj (increasing or decreasing the gate control signal Vg) is determined by the direction of the deviation current. Specifically, when the signal processing unit 223 receives a positive deviation current I2, the adjustment signal Vadj is used to indicate that the gate control signal Vg is increased, and when the signal processing unit 223 receives a negative deviation current I3, the adjustment signal Vadj is used to indicate that the gate control signal Vg is decreased. It can be understood that the adjustment magnitude of the gate control signal Vg is positively correlated with the absolute value of the deviation current corresponding to the adjustment signal Vadj, that is, the larger the absolute value of the deviation current, the larger the adjustment amplitude of the gate control signal Vg, and the smaller the deviation current, the smaller the adjustment amplitude of the gate control signal Vg.

[0094] In order to determine whether the load RL has a short circuit abnormality or an open circuit abnormality, in this embodiment, the abnormality judgment unit 224 includes a first abnormality judgment module 224A and a second abnormality judgment module 224B, wherein the first abnormality judgment module 224A is connected to the first operation module 222B, and the second abnormality judgment module 224B is connected to the second operation module 222C. When the first abnormality judgment module 224A detects that the first operation module 222B outputs a positive deviation current I2, it compares the positive deviation current I2 with the first reference current value IDref1, and outputs a short circuit signal if the positive deviation current I2 is greater than the first reference current value IDref1; similarly, when the second abnormality judgment module 224B detects that the second operation module 222C outputs a negative deviation current I3, it compares the negative deviation current I3 with the second reference current value IDref2, and outputs an open circuit signal if the negative deviation current I3 is greater than the second reference current value IDref2; wherein the above-mentioned preset current threshold includes the first reference current value IDref1 and the second reference current value IDref2.

[0095] Continue to refer to Figure 4 As shown, the first abnormality judgment module 224A includes a second resistor R2, a second four NMOS tube N24, a second five NMOS tube N25, a first constant current source and a first buffer U1; wherein, one end of the second resistor R2 is connected to the output end of the first operation module 222B, and the other end thereof is connected to the drain of the second four NMOS tube N24, the gate of the second four NMOS tube N24 is connected to its drain and the gate of the second five NMOS tube N25, the source of the second four NMOS tube N24 and the source of the second five NMOS tube N25 are both connected to the power ground terminal, the drain of the second five NMOS tube N25 is connected to the first constant current source, the first constant current source is connected to the internal power supply terminal VDD, and the comparison result of the positive bias current I2 flowing through the second five NMOS tube N25 and the first reference current value IDref1 provided by the first constant current source is output through the first buffer U1.

[0096] Optionally, the second resistor R2 is used to convert the positive deviation current I2 into a first deviation voltage for acquisition by the signal processing unit 223, and then output a first adjustment signal. The mirror pair formed by the second four NMOS tubes N24 and the second five NMOS tubes N25 is used to collect the positive deviation current I2 and compare it with the first reference current value IDref1. Exemplarily, in this embodiment, the first buffer U1 can be implemented by an inverter, so that when the positive deviation current I2 is greater than the first reference current value IDref1, the first buffer outputs a high-level signal as a short-circuit signal, indicating that a short-circuit abnormality occurs in the load RL, and when the positive deviation current I2 is less than or equal to the first reference current value IDref1, the first buffer outputs a low-level signal, which indicates that the load RL does not have a short-circuit abnormality.

[0097] Similarly, continue to refer to Figure 4 As shown, the second abnormality judgment module 224B includes a third resistor R3, a first five PMOS tube P15, a first six PMOS tube P16, a second constant current source and a second buffer U2; wherein, one end of the third resistor R3 is connected to the output end of the second operation module 222C, and the other end thereof is connected to the drain of the first five PMOS tube P15, the gate of the first five PMOS tube P15 is connected to its drain and the gate of the first six PMOS tube P16, the source of the first five PMOS tube P15 and the source of the first six PMOS tube P16 are both connected to the internal power supply terminal VDD, the drain of the first six PMOS tube P16 is connected to the second constant current source IDref2, the second constant current source IDref2 is connected to the power ground terminal GND, and the comparison result of the negative deviation current I3 flowing through the first six PMOS tube P16 and the second reference current value IDref2 provided by the second constant current source is output through the second buffer U2.

[0098] Optionally, the third resistor R3 is used to convert the negative deviation current I3 into a second deviation voltage for acquisition by the signal processing unit 223, and then output a second adjustment signal. The mirror pair formed by the first five PMOS tubes P15 and the first six PMOS tubes P16 is used to collect the negative deviation current I3 and compare it with the second reference current value IDref2. Exemplarily, in this embodiment, when the negative deviation current I3 is greater than the second reference current value IDref2, the second buffer outputs a high-level signal as an open-circuit signal, indicating that an open-circuit abnormality occurs in the load RL, and when the negative deviation current I3 is less than or equal to the second reference current value IDref2, the second buffer outputs a low-level signal, which indicates that no open-circuit abnormality occurs in the load RL.

[0099] In the embodiment of the application, the above scheme is used to realize the detection of abnormalities such as load RL short circuit or load RL open circuit based on the clamp circuit 22.

[0100] Optionally, in the above-mentioned first embodiment, in order to improve the working efficiency and detection accuracy of the clamping circuit 22, the power switch Q is preferably in a stable state. If the power switch Q has just been turned on and has not yet entered a stable state, the drain-source voltage value Vds of the power switch Q is relatively small. According to the clamping principle of the clamping circuit 22, the gate control signal Vg needs to be reduced. At this time, the power switch Q cannot be turned on normally, and the drain-source voltage value Vds of the power switch Q cannot be pulled up to the reference voltage value Vref. Therefore, the clamping circuit 22 performs abnormal detection at this time, which may cause the deviation current to be greater than the preset current threshold, resulting in a false detection. Therefore, the present application provides a second embodiment and a third embodiment, by adding an effective condition to the start of the working time of the clamping circuit 22 to improve the working efficiency and detection accuracy of the clamping circuit 22.

[0101] For example, Figure 5 Schematic diagram of the circuit module of the intelligent electronic switch and its peripheral components provided in the second embodiment of the present application. Figure 5 As shown, in this embodiment, the intelligent electronic switch 20 may further include an input terminal INPUT and a first timing circuit 25. The input terminal INPUT is connected to the control circuit 21 and the first timing circuit 25 respectively, and the first timing circuit 25 is connected to the clamping circuit 22.

[0102] Continue to refer to Figure 5 As shown, when the input terminal INPUT receives the start control signal (ON signal), the control circuit 21 controls the power switch Q to turn on and conduct, and at the same time, the first timing circuit 25 starts timing. The first timing circuit 25 outputs a timing arrival signal when the continuous timing duration reaches the first preset duration, and the timing arrival signal is used to trigger the clamp circuit 22 to start working.

[0103] Optionally, the input terminal INPUT is used to connect to a microcontroller, and can receive the switch control signal (ON / OFF signal) from the microcontroller.

[0104] In this embodiment, when the input terminal INPUT receives an on-control signal (ON signal), on the one hand, the on-control signal (ON signal) can be received by the control circuit 21, so that the control circuit 21 outputs a gate control signal Vg to the control terminal of the power switch Q when receiving the on-control signal (ON signal), so as to gradually increase the gate-source voltage value Vgs of the power switch Q, and then when the gate-source voltage value Vgs of the power switch Q is greater than its on-threshold value, the power switch Q is turned on and conducted; on the other hand, the on-control signal (ON signal) can also be received by the first timing circuit 25, so that the first timing circuit 25 is triggered to start timing when receiving the on-control signal (ON signal), that is, the first timing circuit 25 can time the duration for which the control circuit 21 receives the on-control signal and controls the power switch Q to be turned on and conducted based on the on-control signal.

[0105] In practical applications, the time required for the power switch Q to be turned on is related to the gate control signal Vg output by the control circuit 21 to the control end of the power switch Q and the specifications of the power switch Q (mainly the gate-source capacitance of the power switch Q itself). In this embodiment, a first preset time can be preset in the first timing circuit 25 based on the gate control signal Vg of the control end of the power switch Q and the specifications of the power switch Q, that is, after the start control signal is received from the input end INPUT and the first preset time is started, it is considered that the power switch Q has been turned on. Therefore, the first timing circuit 25 outputs a timing arrival signal when the continuous timing time reaches the first preset time, and then triggers the clamping circuit 22 to start working, and then triggers the abnormality detection circuit 23 to start working after the clamping circuit 22 works, which can greatly reduce the problem of being unable to clamp the drain-source voltage value Vds of the power switch Q, and can also avoid the problem of false detection by the abnormality detection circuit 23.

[0106] For example, Figure 6 Schematic diagram of the circuit module of the intelligent electronic switch and its peripheral components provided in the third embodiment of the present application. Figure 6 As shown, in this embodiment, the intelligent electronic switch 20 may further include an input terminal INPUT and a gate-source voltage detection circuit 23. The input terminal INPUT is connected to the control circuit 21 and the gate-source voltage detection circuit 23 respectively, and the gate-source voltage detection circuit 23 is connected to the clamp circuit 22.

[0107] In this embodiment, when the input terminal INPUT receives a start control signal (ON signal), the control circuit 21 controls the power switch Q to start and conduct, and the gate-source voltage detection circuit 23 obtains the gate voltage value Vg and the source voltage value Vs of the power switch Q and obtains the gate-source voltage value Vgs. The gate-source voltage detection circuit 23 outputs an enable signal when the gate-source voltage value Vgs is greater than or equal to the gate-source reference voltage value Vgs_r to enable the clamping circuit 22 to start working.

[0108] Optionally, when the input terminal INPUT receives a turn-on control signal (ON signal), the control circuit 21 can receive the turn-on control signal (ON signal) and output a gate control signal Vg to the control terminal of the power switch Q, so that the gate-source voltage value Vgs of the power switch Q will gradually increase. Therefore, the gate-source voltage detection circuit 23 can detect the increase in the gate-source voltage value Vgs of the power switch Q. When the gate-source voltage value Vgs is greater than or equal to the gate-source reference voltage value Vgs_r, it indicates that the power switch Q has been fully turned on and conducted. At this time, the clamping circuit 22 is enabled to perform voltage clamping and load abnormality detection, which can improve work efficiency and detection accuracy.

[0109] It can be understood that in the above embodiment, the reference voltage value Vref used to clamp the drain-source voltage value Vds can be a reference value preset in the intelligent electronic switch. At this time, the drain-source voltage value Vds can be clamped to the same reference voltage value Vref for different power switches Q, so as to achieve power consumption control of the power switch Q. However, when the intelligent electronic switch is applied to different products or different scenarios, it may be necessary to clamp the drain-source voltage value Vds of the power switch Q to different reference voltage values ​​Vref for better power control. Exemplarily, the reference voltage value can range from 20mv to 50mv. In one embodiment, the reference voltage value is 20mv. In response to this demand, the present application provides a fourth embodiment to set different reference voltage values ​​Vref according to different user needs or scenario requirements.

[0110] For example, Figure 7 Schematic diagram of the circuit module of the intelligent electronic switch and its peripheral components provided in the fourth embodiment of the present application. Figure 7 As shown, in this embodiment, the intelligent electronic switch 20 may further include a reference voltage setting pin SET and a reference voltage setting circuit 24. The reference voltage setting circuit 24 is connected to the clamp circuit 22 and the reference voltage setting pin SET. The reference voltage setting pin SET is also used to be connected to a first resistor R1. The first resistor R1 is used to set the size of the reference voltage value Vref based on the reference voltage setting circuit 24. The larger the resistance of the first resistor R1, the larger the reference voltage value Vref.

[0111] Continue to refer to Figure 7As shown, in this embodiment, the reference voltage setting circuit 24 may include a constant current source I1, one end of which is connected to the internal power supply terminal VDD, which can be understood as the output end of the power supply unit inside the intelligent electronic switch 20, and the other end of the constant current source I1 is connected to the reference voltage setting pin SET, and the reference voltage setting pin SET is also connected to the clamp circuit 22, and is externally connected to the first resistor R1. Therefore, the reference voltage value Vref connected to the clamp circuit 22 is equal to the voltage value at the reference voltage setting pin SET, and the voltage value at the reference voltage setting pin SET is equal to the output current of the constant current source I1 multiplied by the resistance value of the first resistor R1. Therefore, the reference voltage value Vref connected to the clamp circuit 22 is equal to the output current of the constant current source I1 multiplied by the resistance value of the first resistor R1.

[0112] Specifically, after the clamping circuit 22 of the intelligent electronic switch is designed, the current value output by the constant current source I1 is usually unchanged, because the voltage drop across the first resistor R1 can be changed by changing the resistance value of the first resistor R1, that is, the voltage value at the reference voltage setting pin SET can be changed. Exemplarily, when the resistance value of the first resistor R1 increases, the voltage drop across the first resistor R1, that is, the voltage value at the reference voltage setting pin SET increases, and accordingly, the reference voltage value Vref also increases; similarly, when the resistance value of the first resistor R1 decreases, the reference voltage value Vref also decreases.

[0113] The intelligent electronic switch provided in the embodiment of the present application is provided with a reference voltage setting pin and a reference voltage setting circuit, wherein the reference voltage setting pin is used to be connected to a first resistor. Thus, when the intelligent electronic switch is packaged into an integrated circuit chip or a chip product, the value of the internal reference voltage value thereof can be changed by changing the resistance value of the first resistor, thereby clamping the drain-source voltage value of the power switch to a different reference voltage value. The intelligent electronic switch can be applied to different application scenarios, meet different user needs, and enhance the competitiveness of products using the intelligent electronic switch.

[0114] It can be understood that for other parts not recorded in the above embodiment, reference can be made to the records in other embodiments, and this application does not limit them.

[0115] Optionally, based on the above embodiments, the embodiment of the present application further provides an integrated circuit chip, the integrated circuit chip includes the intelligent electronic switch 20 for abnormality detection provided by the above embodiments, that is, the above intelligent electronic switch 20 can be made on the same semiconductor substrate. Among them, the power supply terminal VBAT is a power supply pin, the power ground terminal GND is a power ground pin, and the load output terminal OUT is a load output pin.

[0116] Optionally, other embodiments of the present application further provide a chip product, which may include the intelligent electronic switch 20 for abnormality detection provided by the above embodiments, wherein the components of the intelligent electronic switch 20 except the power switch Q are located on a first integrated circuit chip, and the power switch Q is located on a second integrated circuit chip, that is, the first integrated circuit chip is made on one semiconductor substrate, and the second integrated circuit chip is made on another semiconductor substrate.

[0117] Among them, the power supply terminal VBAT 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 power supply pin and the power ground pin are located on the first integrated circuit chip, and the load output pin is located on the second integrated circuit chip. In addition, the first integrated circuit chip also includes other pins, such as input pins, abnormal output pins, first drive pins, etc., and the second integrated circuit chip also includes other pins, for example, a second drive pin, wherein the first drive pin is respectively connected to the control circuit 21 and the second drive pin, and the second drive pin is connected to the control end of the power switch Q. It can be understood that the first integrated circuit chip and the second integrated circuit chip can also add other pins, omit related pins, or merge related pins as needed. Here, the first integrated circuit chip and the second integrated circuit chip are packaged into one product.

[0118] In addition, in other embodiments of the present application, a car is also provided. The car can be an electric car, such as an electric passenger car or an electric commercial vehicle, or a hybrid car or a fuel car. The car includes a battery 10, a load RL, a microcontroller (not shown) and an intelligent electronic switch 20.

[0119] The battery 10 is generally a storage battery, which provides voltages such as 12V, 24V, 48V, etc., and can also be other types of batteries. The load RL includes at least one of a resistive load, an inductive load, and a capacitive load. The resistive load 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. The inductive load 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 is, for example, a lighting element, such as a xenon arc lamp.

[0120] The microcontroller is connected to the intelligent electronic switch for controlling the intelligent electronic switch. Meanwhile, the intelligent electronic switch feeds back its state and related parameter information, such as abnormal information, to the microcontroller for processing by the microcontroller.

[0121] It is understandable that the intelligent electronic switch and integrated circuit chip of this embodiment are not limited to use in automotive electronics, but can also be used in industrial automation, aerospace and other fields, which will not be elaborated here.

[0122] Those skilled in the art will readily appreciate 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 techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0123] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. An intelligent electronic switch for abnormality detection, characterized in that: It includes a power supply terminal, a power ground terminal, a load output terminal, a power switch, a control circuit and a clamping circuit; The power supply end and the power ground end are used to be connected to a battery, the power switch is used to be connected in series with a load, a first end thereof is connected to the power supply end or the power ground end, a second end thereof is connected to the load output end, and a control end thereof is connected to the control circuit, and the control circuit is used to control the power switch to be turned on or off; The clamping circuit is connected to the source and drain of the power switch, and is used to obtain the drain-source voltage value of the power switch, and output an adjustment signal according to the drain-source voltage value and the connected reference voltage value, so that the control circuit adjusts the gate control signal output to the power switch to clamp the drain-source voltage value to the reference voltage value, and the gate control signal is positively correlated with the load current flowing through the power switch; The clamp circuit is also used to collect a deviation voltage value between the drain-source voltage value and the reference voltage value, and output an abnormal signal when the deviation voltage value is greater than a preset voltage threshold, wherein the abnormal signal is used to indicate a load abnormality.

2. The intelligent electronic switch according to claim 1, characterized in that: The clamp circuit includes a drain-source voltage detection unit, an operation processing unit, a signal processing unit and an abnormality judgment unit; The input end of the drain-source voltage detection unit is respectively connected to the drain and source of the power switch, and the output end thereof is connected to the operation processing unit. The operation processing unit is also used to access the reference voltage value. The operation processing unit is connected to the signal processing unit and the abnormality judgment unit; The drain-source voltage detection unit is used to obtain the drain voltage value and the source voltage value of the power switch and output the drain-source voltage value, the operation processing unit compares the drain-source voltage value with the reference voltage value and outputs a deviation voltage, the signal processing unit generates the adjustment signal based on the deviation voltage, and the abnormality judgment unit compares the deviation voltage with a preset voltage threshold and outputs an abnormality signal when the deviation voltage is greater than the preset voltage threshold.

3. The intelligent electronic switch according to claim 2, characterized in that: The operation processing unit is also used to output a deviation current corresponding to the deviation voltage according to the drain-source voltage value and the reference voltage value, the signal processing unit generates the adjustment signal based on the deviation current, and the abnormality judgment unit compares the deviation current with a preset current threshold and outputs an abnormal signal when the deviation current is greater than the preset current threshold.

4. The intelligent electronic switch according to claim 3, characterized in that: The operation processing unit includes a voltage-current conversion module, a first operation module and a second operation module, and the deviation current includes a positive deviation current and a negative deviation current; The voltage-current conversion module has one input end connected to the drain-source voltage detection unit, another input end thereof is used to access the reference voltage value, and an output end thereof is respectively connected to the first operation module and the second operation module, and the first operation module and the second operation module are respectively connected to the signal processing unit and the abnormality judgment unit; The voltage-current conversion module is used to convert the drain-source voltage value into a first current value, and convert the reference voltage value into a reference current value, and output both to the first operation module and the second operation module; When the drain-source voltage value is greater than the reference voltage value, the first current value is less than the reference current value, the first operation module outputs a positive deviation current, and the second operation module has no output; when the drain-source voltage value is less than the reference voltage value, the first current value is greater than the reference current value, the first operation module has no output, and the second operation module outputs a negative deviation current.

5. The intelligent electronic switch according to claim 4, characterized in that: The signal processing unit outputs a first adjustment signal when detecting that the first operation module outputs a positive deviation current to instruct the control circuit to increase the output gate control signal, and outputs a second adjustment signal when detecting that the second operation module outputs a negative deviation current to instruct the control circuit to decrease the output gate control signal.

6. The intelligent electronic switch according to claim 4, characterized in that: The abnormality judgment unit includes a first abnormality judgment module and a second abnormality judgment module, the first abnormality judgment module is connected to the first operation module, and the second abnormality judgment module is connected to the second operation module; When the first abnormality judgment module detects that the first operation module outputs the positive deviation current, the first abnormality judgment module compares the positive deviation current with a first reference current value, and outputs a short-circuit signal if the positive deviation current is greater than the first reference current value; When the second abnormality judgment module detects that the second operation module outputs the negative deviation current, the second abnormality judgment module compares the negative deviation current with a second reference current value, and outputs an open circuit signal if the negative deviation current is greater than the second reference current value; Wherein, the preset current threshold includes the first reference current value and the second reference current value.

7. The intelligent electronic switch according to any one of claims 1 to 6, characterized in that: Also includes an input terminal and a first timing circuit; The input end is connected to the control circuit and the first timing circuit respectively, and the first timing circuit is connected to the clamping circuit; When the input terminal receives a start control signal, the control circuit controls the power switch to turn on, and at the same time, the first timing circuit starts timing; The first timing circuit outputs a timing arrival signal when the continuous timing duration reaches a first preset duration, so that the clamping circuit starts to work.

8. The intelligent electronic switch according to any one of claims 1 to 6, characterized in that: Also included is an input terminal and a gate-source voltage detection circuit; The input end is connected to the control circuit and the gate-source voltage detection circuit respectively, and the gate-source voltage detection circuit is connected to the clamping circuit; When the input end receives a start control signal, the control circuit controls the power switch to start conducting. At the same time, the gate-source voltage detection circuit obtains the gate voltage value and the source voltage value of the power switch and obtains the gate-source voltage value, and outputs an enable signal when the gate-source voltage value is greater than or equal to the gate-source reference voltage value, so that the clamping circuit starts working.

9. The intelligent electronic switch according to any one of claims 1 to 6, characterized in that: It also includes a reference voltage setting pin and a reference voltage setting unit, wherein the reference voltage setting unit is connected to the clamp circuit and the reference voltage setting pin, and the reference voltage setting pin is also used to be connected to a first resistor, and the first resistor is used to set the reference voltage value based on the reference voltage setting unit. The larger the resistance of the first resistor is, the larger the reference voltage value is.

10. The intelligent electronic switch according to any one of claims 1 to 6, characterized in that: When the power switch operates in the saturation region and the drain-source voltage value of the power switch is clamped to the reference voltage value, the greater the load current flowing through the power switch, the greater the gate control signal, and the smaller the internal resistance value of the power switch.

11. An integrated circuit chip, characterized in that: It comprises an intelligent electronic switch for abnormality detection as described in any one of claims 1 to 10, wherein the power supply end is a power supply pin, the power ground end is a power ground pin, and the load output end is a load output pin.

12. A chip product, characterized in that: An intelligent electronic switch for abnormality detection according to any one of claims 1 to 10, 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, and the load output end is a load output pin. The power supply pin and the power ground pin are located on a first integrated circuit chip, and the load output pin is located on a second integrated circuit chip.

13. A car, characterized in that: An intelligent electronic switch for abnormality detection according to any one of claims 1 to 10, or an integrated circuit chip according to claim 11, or a chip product according to claim 12; It also includes a battery, a load and a microcontroller, wherein the positive electrode of the battery is connected to the power supply terminal, the negative electrode of the battery 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, and the microcontroller is connected to the intelligent electronic switch.

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