High-side driving circuit and device

Abstract

The invention discloses a high-side driving circuit and device, and relates to the technical field of electronic circuits, the high-side driving circuit comprises a main switching circuit, a sampling resistor, an amplifying circuit, an auxiliary switching circuit and a microcontroller, the microcontroller is internally provided with a comparator, a digital-to-analog converter and an interrupt controller, the in-phase end of the comparator is connected with the output end of the amplifying circuit, and the in-phase end of the digital-to-analog converter is connected with the output end of the auxiliary switching circuit. The anti-phase end of the comparator is connected with the output end of the digital-to-analog converter, and the input end of the interrupt controller is connected with the output end of the comparator; the digital-to-analog converter is used for outputting an adjustable reference voltage, the comparator is used for outputting a comparison level signal according to the reference voltage and an amplified voltage output by the amplifying circuit, and the interrupt controller is used for controlling the auxiliary switch circuit to be switched on or switched off according to the comparison level signal. And further, the main switch circuit is controlled to be switched on or switched off. The over-current protection circuit has the characteristics of fast response, low cost and high reliability during over-current protection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic circuits, in particular to a high-side drive circuit and device. BACKGROUND

[0002] The high-side drive circuit refers to a circuit structure in which a switching element (such as a MOSFET) is arranged on the power supply side for controlling the on-off of a load, and the core principle thereof is to realize the on-off or power regulation of a load current by controlling the on-off of the switching element.

[0003] In the field of overcurrent protection of the high-side drive circuit, the prior art generally adopts a discrete device implementation scheme, that is, a reference voltage is generated through a resistance dividing network, and a protection path is constructed by cooperating with a special current detection chip and an optical coupling isolating device.

[0004] However, the above scheme at least has the following defects: Slow response speed: the optical coupling isolation delay (2-10 μs) is superimposed on the processing delay of the discrete comparator, resulting in a long protection response time, which is difficult to meet the real-time requirements of high-speed application scenarios (such as motor drive and fast charging power supply); High cost: the total cost of the special current detection chip (5-15 yuan), discrete comparator and optical coupling peripheral device is high (> 5 yuan); Low reliability: the large number of peripheral devices leads to complex wiring, large PCB area and high EMI risk.

[0005] Low current protection threshold precision and non-adjustable: the reference voltage is generated by resistance division, and is affected by the tolerance of the elements and devices, the precision is only ± 5%-± 10%, and the current protection threshold is fixed after the design is completed, and cannot be corrected in real time according to the load dynamic characteristics (such as motor starting current change) or working condition requirements (such as overload protection strategy adjustment). SUMMARY

[0006] Embodiments of the present application provide a high-side drive circuit and device to solve the technical problems of slow response speed, high cost and poor reliability when the existing high-side drive circuit performs overcurrent protection in the related art.

[0007] In a first aspect, a high-side drive circuit is provided, comprising: a main switching circuit, a sampling resistor, an amplification circuit, an auxiliary switching circuit and a microcontroller; The first end of the main switching circuit is connected with the positive electrode of the power supply, the second end of the main switching circuit is connected with the first end of the sampling resistor, the second end of the sampling resistor is connected with the load, the two input ends of the amplification circuit are connected with the first end and the second end of the sampling resistor respectively, and the auxiliary switching circuit is connected with the main switching circuit. The microcontroller is built-in with a comparator, a digital-to-analog converter and an interrupt controller, the non-inverting terminal of the comparator is connected with the output terminal of the amplification circuit, the inverting terminal of the comparator is connected with the output terminal of the digital-to-analog converter, the input terminal of the interrupt controller is connected with the output terminal of the comparator; The digital-to-analog converter is used for outputting an adjustable reference voltage, the comparator is used for outputting a comparison level signal according to the reference voltage and the amplification voltage output by the amplification circuit, and the interrupt controller is used for controlling the conduction or disconnection of the auxiliary switch circuit, thereby controlling the conduction or disconnection of the main switch circuit.

[0008] In some embodiments, the main switch circuit comprises a first switch, a first resistor and a second resistor, the first terminal of the first switch is connected with the positive pole of the power supply, the second terminal of the first switch is connected with the first terminal of the sampling resistor, the first terminal of the first resistor is connected with the first terminal of the first switch, the second terminal of the first resistor is connected with the third terminal of the first switch, the first terminal of the second resistor is connected with the third terminal of the first switch, and the second terminal of the second resistor is connected with the auxiliary switch circuit.

[0009] In some embodiments, the high-side drive circuit further comprises: The anti-reverse circuit is arranged between the first terminal of the main switch circuit and the positive pole of the power supply.

[0010] In some embodiments, the anti-reverse circuit comprises a second switch, a third resistor and a voltage stabilizing tube, the first terminal of the second switch is connected with the first terminal of the first switch, the second terminal of the second switch is connected with the positive pole of the power supply, the third terminal of the second switch is connected with the first terminal of the third resistor, the second terminal of the third resistor is grounded, the negative pole of the voltage stabilizing tube is connected with the first terminal of the second switch, and the positive pole of the voltage stabilizing tube is connected with the first terminal of the third resistor.

[0011] In some embodiments, the first switch and the second switch are both PMOS switch tubes.

[0012] In some embodiments, the auxiliary switch circuit comprises a third switch, a fourth resistor and a fifth resistor, the first terminal of the third switch is connected with the second terminal of the second resistor, the second terminal of the third switch is grounded, the first terminal of the fourth resistor is connected with the microcontroller, the second terminal of the fourth resistor is connected with the second terminal of the third switch, the first terminal of the fifth resistor is connected with the second terminal of the third switch, and the second terminal of the fifth resistor is grounded.

[0013] In some embodiments, the third switch is an NPN triode.

[0014] In some embodiments, the amplification circuit comprises a current sense amplifier, a sixth resistor and a first capacitor, the non-inverting terminal of the current sense amplifier is connected with the first end of the sampling resistor, the inverting terminal of the current sense amplifier is connected with the second end of the sampling resistor, the output terminal of the current sense amplifier is connected with the first end of the sixth resistor, the second end of the sixth resistor is connected with the inverting terminal of the comparator, the first end of the first capacitor is connected with the second end of the sixth resistor, and the second end of the first capacitor is grounded.

[0015] In some embodiments, the sampling resistor is a resistor with a resistance error within ±0.5%.

[0016] In a second aspect, a high-side driving device is provided, comprising the high-side driving circuit as described above.

[0017] The technical scheme provided by the present application has the following beneficial effects: The high-side driving circuit and device provided by the embodiments of the present application are provided with a sampling resistor, an amplification circuit, an auxiliary switch circuit and a microcontroller, wherein the microcontroller is internally provided with a comparator, a digital-to-analog converter and an interrupt controller, the response time is reduced (<5 microseconds) by using the comparator, the digital-to-analog converter and the interrupt controller in the microcontroller, the response speed is improved by 2-5 times compared with the traditional scheme, only a low-cost current sense amplifier and internal resources of the microcontroller are needed, the total cost is reduced, the cost can be reduced by 70-80%, the peripheral devices are reduced by more than 60%, the PCB area is reduced, the wiring is simplified, the EMI performance is improved, and the reliability is greatly improved. In addition, the digital precise setting of the reference voltage can be realized by the digital-to-analog converter in the microcontroller, the precision reaches the resolution level of the digital-to-analog converter (12-bit DAC precision 0.024%), the precision is improved by 50-100 times compared with the traditional resistance voltage division setting reference voltage scheme (precision ±5% to ±10%), and the internal digital-to-analog converter can support real-time adjustment of the reference voltage (corresponding to the overcurrent protection threshold) to adapt to different load characteristics and working conditions. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 A principle block diagram of a high-side driving circuit provided by the embodiments of the present application is provided. Figure 2 An internal resource configuration diagram of a microcontroller provided by the embodiments of the present application is provided. Figure 3 A circuit diagram of a high-side driving circuit provided in an embodiment of the present invention; Figure 4 A timing diagram for overcurrent protection of a high-side drive circuit provided in an embodiment of the present invention; Figure 5 The current waveform diagram is provided for overcurrent protection of a high-side drive circuit according to an embodiment of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This invention provides a high-side drive circuit that solves the technical problems of slow response speed, high cost, and poor reliability in existing high-side drive circuits when performing overcurrent protection.

[0022] See Figure 1 As shown, an embodiment of the present invention provides a high-side driving circuit, including: a main switching circuit, a sampling resistor, an amplifier circuit, an auxiliary switching circuit, and a microcontroller (MCU).

[0023] The first terminal of the main switch circuit is connected to the positive terminal of the power supply, the second terminal of the main switch circuit is connected to the first terminal of the sampling resistor, the second terminal of the sampling resistor is connected to the load, the two input terminals of the amplifier circuit are connected to the first and second terminals of the sampling resistor respectively, and the auxiliary switch circuit is connected to the main switch circuit.

[0024] The microcontroller has a built-in comparator (CMP), a digital-to-analog converter (DAC), and an interrupt controller. The non-inverting input of the comparator is connected to the output of the amplifier circuit, the inverting input of the comparator is connected to the output of the DAC, and the input of the interrupt controller is connected to the output of the comparator. Figure 2 This is a diagram showing the internal resource configuration of a microcontroller.

[0025] The digital-to-analog converter is used to output an adjustable reference voltage, the comparator is used to output a comparison level signal based on the reference voltage and the amplified voltage output by the amplifier circuit, and the interrupt controller is used to control the auxiliary switch circuit to turn on or off based on the comparison level signal, thereby controlling the main switch circuit to turn on or off.

[0026] Specifically, when the current flowing through the sampling resistor does not exceed the current threshold, the reference voltage is less than the amplified voltage output by the amplifier circuit. The comparator outputs a comparison level signal (low level), and the interrupt controller outputs a command based on the comparison level signal (low level) to turn on the auxiliary switch circuit, thereby turning on the main switch circuit and energizing the load. The auxiliary switch circuit is connected to a GPIO (General Purpose Input / Output) port of the microcontroller. The interrupt controller outputs a command to the GPIO controller of the microcontroller, and the GPIO controller outputs a control signal to the auxiliary switch circuit through this GPIO port, turning on the auxiliary switch circuit.

[0027] When the current flowing through the sampling resistor exceeds the current threshold, and the reference voltage is not less than the amplified voltage output by the amplifier circuit, the comparator outputs a comparison level signal (high level). Based on this high level signal, the interrupt controller outputs a command to disconnect the auxiliary switch circuit, thereby disconnecting the main switch circuit and de-energizing the load, thus achieving overcurrent protection. Similarly, the interrupt controller outputs a command to the microcontroller's GPIO controller, which outputs a control signal to the auxiliary switch circuit via the GPIO, causing the auxiliary switch circuit to disconnect.

[0028] The high-side drive circuit in this embodiment of the invention includes a sampling resistor, an amplifier circuit, an auxiliary switching circuit, and a microcontroller. The microcontroller integrates a comparator, a digital-to-analog converter (DAC), and an interrupt controller. Utilizing these internal components, the response time is reduced (<5μs), a 2-5 times improvement over traditional solutions. It requires only a low-cost current-sensing amplifier and the microcontroller's internal resources, resulting in a 70-80% reduction in total cost. External components are reduced by over 60%, PCB area is reduced, wiring is simplified, EMI performance is improved, and reliability is significantly enhanced. Furthermore, the microcontroller's internal DAC enables precise digital setting of the reference voltage, achieving DAC resolution (0.024% accuracy for a 12-bit DAC). Compared to traditional resistor-divided reference voltage settings (±5%~±10% accuracy), this represents a 50-100 times improvement in accuracy. The internal DAC also supports real-time software adjustment of the reference voltage (corresponding to the overcurrent protection threshold), adapting to different load characteristics and operating conditions.

[0029] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 3As shown, the main switching circuit includes a first switch Q1, a first resistor R1, and a second resistor R2. The first terminal of the first switch Q1 is connected to the positive terminal of the power supply, the second terminal of the first switch Q1 is connected to the first terminal of the sampling resistor, the first terminal of the first resistor R1 is connected to the first terminal of the first switch Q1, the second terminal of the first resistor R1 is connected to the third terminal of the first switch Q1, the first terminal of the second resistor R2 is connected to the third terminal of the first switch Q1, and the second terminal of the second resistor R2 is connected to the auxiliary switching circuit. The first switch Q1 is a PMOS transistor, and its first, second, and third terminals are the source, drain, and gate, respectively.

[0030] When the current flowing through the sampling resistor Rc is normal, the interrupt controller of the microcontroller U1 outputs a command to turn on the auxiliary switch circuit, ground the second terminal of the second resistor R2, and make the gate voltage of the first switch Q1 lower than the source voltage (Vgs<0), so that the first switch Q1 is turned on and the load is powered on. When the current flowing through the sampling resistor Rc exceeds the current threshold, the output command of the interrupt controller of the microcontroller U1 causes the auxiliary switch circuit to be disconnected, the second end of the second resistor R2 to be left floating, the gate voltage of the first switch Q1 to be equal to the source voltage, the first switch Q1 is disconnected, the load is de-energized, and overcurrent protection is achieved.

[0031] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 3 As shown, the high-side drive circuit also includes an anti-reverse circuit, which is located between the first terminal of the main switch circuit and the positive terminal of the power supply. The anti-reverse circuit can prevent the device from being damaged due to reverse power supply connection.

[0032] Specifically, the anti-reverse circuit includes a second switch Q2, a third resistor R3, and a Zener diode ZD. The first terminal of the second switch Q2 is connected to the first terminal of the first switch Q1, the second terminal of the second switch Q2 is connected to the positive terminal of the power supply, the third terminal of the second switch Q2 is connected to the first terminal of the third resistor R3, and the second terminal of the third resistor R3 is grounded. The negative terminal of the Zener diode ZD is connected to the first terminal of the second switch Q2, and the positive terminal of the Zener diode ZD is connected to the first terminal of the third resistor R3. The second switch Q2 is a PMOS switch, and the first, second, and third terminals of the first switch Q1 are the source, drain, and gate, respectively.

[0033] When the positive terminal of the power supply is normally connected: the body diode of the second switch Q2 conducts first, and then the source voltage changes from 0V to (VCC-0.7). At this time, Vgs=0-(VCC-0.7)=-VCC+0.7, where VCC is the power supply voltage. Generally, the gate conduction threshold of a PMOS switch is -1~2V, while the voltage difference of most power supplies exceeds this value. Therefore, Vgs exceeds the gate conduction threshold, and the second switch Q2 is fully turned on. As the second switch Q2 is fully turned on, the potential difference between the drain and source of the second switch Q2 (internal resistance multiplied by the current flowing through it) is pulled low. This value is generally very small, much less than 0.7V. The body diode of the second switch Q2 is short-circuited and turned off, and the second switch Q2 continues to conduct.

[0034] When the positive terminal of the power supply is reversed: the body diode of the second switch Q2 is reversed and remains in the off state. Even with a 0Ω load, the source potential remains equal to the gate potential, and the second switch Q2 remains in the off state, thus shutting down the circuit and providing reverse connection protection. Additionally, the Zener diode ZD is used to prevent damage to the gate of the second switch Q2 due to excessive power supply voltage.

[0035] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 3 As shown, the auxiliary switching circuit includes a third switch Q3, a fourth resistor R4, and a fifth resistor R5. The first terminal of the third switch Q3 is connected to the second terminal of the second resistor R2, and the second terminal of the third switch Q3 is grounded. The first terminal of the fourth resistor R4 is connected to the microcontroller (GPIO), and the second terminal of the fourth resistor R4 is connected to the second terminal of the third switch Q3. The first terminal of the fifth resistor R5 is connected to the second terminal of the third switch Q3, and the second terminal of the fifth resistor R5 is grounded. The third switch Q3 is an NPN transistor, and its first, second, and third terminals are the collector, emitter, and base, respectively.

[0036] When the current flowing through the sampling resistor Rc is normal, the interrupt controller of the microcontroller U1 outputs an instruction, outputting a high level through the corresponding GPIO, the third switch Q3 is turned on, the collector voltage is pulled low (close to 0V), the second end of the second resistor R2 is grounded, making the gate voltage of the first switch Q1 lower than the source voltage (Vgs<0), the first switch Q1 is turned on, and the load is powered on; When the current flowing through the sampling resistor exceeds the current threshold, the interrupt controller of the microcontroller U1 outputs an instruction, which outputs a low level through the corresponding GPIO. The third switch Q3 is turned off, the second end of the second resistor R2 is left floating, so that the gate voltage of the first switch Q1 is equal to the source voltage. The first switch Q1 is turned off, the load is de-energized, and overcurrent protection is achieved.

[0037] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 3 As shown, the amplification circuit includes a current-sensing amplifier U2, a sixth resistor R6, and a first capacitor C1. The inverting input of the current-sensing amplifier U2 is connected to the first terminal of the sampling resistor R6, the non-inverting input of the current-sensing amplifier U2 is connected to the second terminal of the sampling resistor R6, the output terminal of the current-sensing amplifier U2 is connected to the first terminal of the sixth resistor R6, the second terminal of the sixth resistor R6 is connected to the non-inverting input of the comparator, the first terminal of the first capacitor C1 is connected to the second terminal of the sixth resistor R6, and the second terminal of the first capacitor C1 is grounded. The current-sensing amplifier U2 can be of models such as INA180 or LM358.

[0038] The sampling resistor Rc is a low-value resistor (e.g., 5mΩ), and the voltage drop across it is V = I × Rc. ， The voltage drop V is proportional to the load current I. The current-sensing amplifier U2 amplifies the small voltage signal and inputs it to the comparator of the microcontroller to achieve accurate acquisition and digital processing of the current signal. The output voltage V_out of the current-sensing amplifier U2 is V × Gain (amplification factor, ensuring that the output voltage V_out is within the input range of the microcontroller's comparator). Correspondingly, assuming the overcurrent protection threshold is I_th, the reference voltage V_ref is determined according to I_th = V_ref / (Rc × Gain). Conversely, the microcontroller adjusts the output reference voltage V_ref of its internal digital-to-analog converter through software to achieve real-time adjustment of the overcurrent protection threshold.

[0039] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 3 As shown, the sampling resistor is a resistor with a resistance error within ±0.5%, which can ensure the accuracy of current acquisition.

[0040] The working principle of the high-side driving circuit in the embodiments of the present invention is further illustrated below with several examples.

[0041] 1. Overcurrent protection example: 5A overcurrent protection setting (12V / 5A motor load) Sampling resistor: Rc = 5mΩ; Current sensor amplifier gain: Gain = 200; Overcurrent protection threshold: I_th = 5A; Reference voltage: V_ref = I_th × Rc × Gain = 5A × 0.005Ω × 200 = 5V; Microcontroller (MCU) configuration: Digital-to-analog converter (DAC) configuration: 12-bit resolution, output 5V reference voltage; CMP comparator configuration: The non-inverting input is connected to the output of the current sensor amplifier, and the inverting input is connected to the output of the digital-to-analog converter (DAC). Interrupt controller configuration: rising edge triggered; Work process: Normal operation: Load current 3A → sampling resistor voltage drop 15mV → after amplification 3V < 5V → comparator output low level (interrupt not triggered); Overcurrent protection: Load current 6A → sampling resistor voltage drop 30mV → after amplification 6V>5V → comparator output high level → trigger interrupt (output low level through GPIO to the base of the third switch Q3) → turn off the first switch Q1 → protection response time <5μs.

[0042] Figure 4 This is a timing diagram illustrating the operation of an overcurrent protection embodiment. Figure 5 The current waveform diagram shows the operation of an overcurrent protection embodiment.

[0043] 2. Threshold Adjustment Example: Dynamic Threshold Adjustment (Adapting to Load Characteristic Changes) Start-up phase: Set a higher threshold of 8A to allow for inrush current; Digital-to-analog converter (DAC) output: V_ref = 8A × 0.005Ω × 200 = 8V Operation adjustment: After stable operation: The software adjusts the digital-to-analog converter (DAC) output to 5V, and the threshold is reduced to 5A; Adjustment time: <1ms, achieving a smooth transition; Fault recovery: After the overcurrent protection is triggered, it will attempt to restart after a 100ms delay. The protection strategy can be dynamically adjusted according to the fault frequency.

[0044] 3. Multi-channel application example (input voltage fluctuation 9V-16V); Microcontroller operating voltage: 5V (regulated by LDO); Current sensor amplifier power supply: 5V, ensuring output range of 0-5V; First switch Q1: Adapts to a power supply voltage range of 9V-16V; Temperature compensation: Temperature coefficient of sampling resistance: ±50ppm / °C; Temperature coefficient of the digital-to-analog converter (DAC) inside the microcontroller: ±20ppm / °C; Overall threshold temperature drift: <±0.1% / °C.

[0045] This invention also provides a high-side driving device, including the aforementioned high-side driving circuit.

[0046] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0047] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0048] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

Claims

1. A high-side driver circuit, comprising: The high-side drive circuit comprises a main switch circuit, a sampling resistor, an amplification circuit, an auxiliary switch circuit and a microcontroller. A first end of the main switch circuit is connected with a positive electrode of a power supply, a second end of the main switch circuit is connected with a first end of the sampling resistor, a second end of the sampling resistor is connected with a load, two input ends of the amplification circuit are connected with the first end and the second end of the sampling resistor respectively, and the auxiliary switch circuit is connected with the main switch circuit. The microcontroller is internally provided with a comparator, a digital-to-analog converter and an interrupt controller, a non-inverting input end of the comparator is connected with an output end of the amplification circuit, an inverting input end of the comparator is connected with an output end of the digital-to-analog converter, and an input end of the interrupt controller is connected with an output end of the comparator. The digital-to-analog converter is used for outputting an adjustable reference voltage, the comparator is used for outputting a comparison level signal according to the reference voltage and an amplification voltage output by the amplification circuit, and the interrupt controller is used for controlling the auxiliary switch circuit to be turned on or turned off, so as to control the main switch circuit to be turned on or turned off.

2. The high-side drive circuit according to claim 1, wherein the main switch circuit comprises a first switch, a first resistor and a second resistor, a first end of the first switch is connected with a positive electrode of a power supply, a second end of the first switch is connected with a first end of the sampling resistor, a first end of the first resistor is connected with the first end of the first switch, a second end of the first resistor is connected with a third end of the first switch, a first end of the second resistor is connected with the third end of the first switch, and a second end of the second resistor is connected with the auxiliary switch circuit. The high-side drive circuit further comprises an anti-reverse circuit, which is arranged between the first end of the main switch circuit and the positive electrode of the power supply.

4. The high-side drive circuit according to claim 3, wherein the anti-reverse circuit comprises a second switch, a third resistor and a voltage stabilizing tube, a first end of the second switch is connected with the first end of the first switch, a second end of the second switch is connected with the positive electrode of the power supply, a third end of the second switch is connected with a first end of the third resistor, a second end of the third resistor is grounded, a negative electrode of the voltage stabilizing tube is connected with the first end of the second switch, and a positive electrode of the voltage stabilizing tube is connected with the first end of the third resistor.

3. The high-side driver circuit of claim 2, wherein, The first switch and the second switch are both PMOS switch tubes.

6. The high-side drive circuit according to claim 2, wherein the auxiliary switch circuit comprises a third switch, a fourth resistor and a fifth resistor, a first end of the third switch is connected with the second end of the second resistor, a second end of the third switch is grounded, a first end of the fourth resistor is connected with the microcontroller, a second end of the fourth resistor is connected with the second end of the third switch, a first end of the fifth resistor is connected with the second end of the third switch, and a second end of the fifth resistor is grounded. The third switch is an NPN triode.

8. The high-side drive circuit according to claim 1, wherein 5. The high-side driver circuit of claim 4, wherein: ​ ​ ​ 7. The high-side driver circuit of claim 6, wherein: ​ ​ The amplification circuit comprises a current detection amplifier, a sixth resistor and a first capacitor, an inverting terminal of the current detection amplifier is connected with a first terminal of the sampling resistor, a non-inverting terminal of the current detection amplifier is connected with a second terminal of the sampling resistor, an output terminal of the current detection amplifier is connected with a first terminal of the sixth resistor, a second terminal of the sixth resistor is connected with a non-inverting terminal of the comparator, a first terminal of the first capacitor is connected with the second terminal of the sixth resistor, and a second terminal of the first capacitor is grounded.

9. The high-side driver circuit of claim 1, wherein: The sampling resistor is a resistor with a resistance error within ±0.5%.

10. A high-side driver device, characterized by The high-side drive circuit comprises the high-side drive circuit according to any one of claims 1-9.

Images