Slope control circuit of high-side switch and electronic product

Abstract

The application provides a slope control circuit of a high-side switch and an electronic product, comprising: a detection module, which detects a load current of a high-side switch in a switch module and outputs a detection voltage; an operational amplifier, which receives the detection voltage at a first input end and a reference voltage at a second input end and outputs a difference between the two; a first capacitor, which is connected to a control end of the high-side switch at one end and to a first bias voltage at the other end; and an adjustment module, which controls a rate at which the high-side switch is turned on or turned off, so as to make a rising or falling slope of a voltage at an output end of the high-side switch constant. The slope control circuit of the high-side switch and the electronic product control the rising slope and the falling slope of the gate voltage of the high-side switch to reach a dynamic balance through a negative feedback loop; further, the rising slope and the falling slope of the gate voltage of the high-side switch are accurately controlled through a bias current, so as to improve electromagnetic compatibility of a circuit in which the high-side switch is located.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of integrated circuits, and in particular to a slope control circuit of a high-side switch and an electronic product. BACKGROUND

[0002] With the rapid increase of clock frequency of modern digital devices using low signal voltage, the electromagnetic compatibility (EMC) problem becomes more and more important, which refers to the ability of a device or system to function in its electromagnetic environment without causing intolerable electromagnetic disturbance to any equipment in its environment, i.e. to meet two requirements: on the one hand, the electromagnetic disturbance (EMD) generated by the device in the normal operation process cannot exceed a certain limit value; on the other hand, the device has a certain degree of immunity to electromagnetic disturbance in the environment, i.e. electromagnetic susceptibility (EMS).

[0003] Among them, the electromagnetic compatibility (EMC) problem of the power switch is due to the generation of rapidly changing current and voltage (i.e. dv / dt and di / dt) in the high-voltage and large-current switching state, which leads to strong harmonic interference and peak interference. These interference signals not only affect the normal operation of the circuit where the power switch is located, but also may affect other electronic systems through conduction, radiation and crosstalk; therefore, EMC design is crucial for circuits with power switches.

[0004] How to improve the electromagnetic compatibility of circuits with power switches has become one of the problems to be solved by those skilled in the art.

[0005] It should be noted that the above introduction to the technical background is only to facilitate the clear and complete description of the technical solutions of the present application, and to facilitate the understanding of those skilled in the art. The above technical solutions cannot be considered as known to those skilled in the art merely because they are described in the background section of the present application. SUMMARY

[0006] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a slope control circuit of a high-side switch and an electronic product, which is used to solve the electromagnetic compatibility problem of the high-side switch in the prior art.

[0007] To achieve the above object and other related objects, the present application provides a slope control circuit of a high-side switch, which at least comprises:

[0008] The switch module, the detection module, the operational amplifier, the first capacitor and the adjustment module;

[0009] The detection module is connected to the switch module, detects the load current of the high-side switch in the switch module, and outputs a detection voltage;

[0010] The first input end of the operational amplifier receives the detection voltage, the second input end receives a reference voltage, and the difference between the two is outputted;

[0011] One end of the first capacitor is connected to the control end of the high-side switch, and the other end is connected to a first bias voltage;

[0012] The adjustment module is connected to the control end of the high-side switch and the output end of the operational amplifier, receives a switch control signal, controls the high-side switch to turn on or turn off based on the switch control signal, and controls the rate of turning on or turning off of the high-side switch based on the difference and the charge and discharge of the first capacitor, so as to make the rising or falling slope of the output end voltage of the high-side switch constant.

[0013] Optionally, the switch module comprises a high-side switch, a load and a first resistor;

[0014] The first end of the high-side switch is connected to a first power supply voltage, the second end is grounded via the load, and the control end is connected to the first capacitor and the adjustment module;

[0015] One end of the first resistor is connected to the control end of the high-side switch, and the other end is connected to the second end of the high-side switch.

[0016] Optionally, the detection module comprises a current detection unit and a second resistor;

[0017] The first end of the current detection unit is connected to a first power supply voltage, the second end is grounded via the second resistor, and the third end and the fourth end are respectively connected to the control end and the output end of the high-side switch; the second end of the current detection unit outputs the detection voltage.

[0018] Optionally, the non-inverting input end of the operational amplifier is connected to the detection voltage, the inverting input end is connected to the reference voltage, and the output end outputs the difference.

[0019] Optionally, the operational amplifier comprises a first PNP transistor, a second PNP transistor, a first PMOS transistor, a second PMOS transistor, a third PMOS transistor, a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, a fourth NMOS transistor, a second capacitor and a third resistor;

[0020] The source of the first PMOS tube is connected with a second power voltage, the gate is connected with a second bias voltage, and the drain is connected with the emitter of the first PNP transistor and the second PNP transistor; the base of the first PNP transistor and the second PNP transistor is respectively the inverting input terminal and the non-inverting input terminal of the operational amplifier;

[0021] The source of the second PMOS tube and the third PMOS tube is connected with the second power voltage, and the gate is connected together and connected with the drain of the second PMOS tube;

[0022] The drain of the first NMOS tube is connected with the drain of the second PMOS tube, the gate receives a third bias voltage, and the source is connected with the drain of the second NMOS tube and the collector of the second PNP transistor; the gate of the second NMOS tube receives a fourth bias voltage, and the source is grounded;

[0023] The drain of the third NMOS tube is connected with the drain of the third PMOS tube and is the output terminal of the operational amplifier, the gate receives a fifth bias voltage, and the source is connected with the drain of the fourth NMOS tube and the collector of the first PNP transistor; the gate of the fourth NMOS tube receives the sixth bias voltage, and the source is grounded;

[0024] The second capacitor and the third resistor constitute a series structure, and the two ends of the series structure are respectively connected with the drain of the third NMOS tube and the gate of the fourth NMOS tube.

[0025] More optionally, the third bias voltage is equal to the fifth bias voltage, and the fourth bias voltage is equal to the sixth bias voltage.

[0026] Optionally, the adjusting module comprises a first switch, a second switch, a first constant current source, a second constant current source and an adjusting tube.

[0027] The first switch and the first constant current source are connected in series between a third power voltage and the control end of the high-side switch.

[0028] The second switch and the second constant current source are connected in series between the control end of the high-side switch and the ground.

[0029] The first end of the adjusting tube is connected with the control end of the high-side switch, the second end is grounded, and the control end receives the difference value.

[0030] More optionally, the descending slope of the output voltage of the high-side switch satisfies:

[0031]

[0032] Wherein, V out is the output voltage of the high-side switch, VA is the gate voltage of the high-side switch, I2 is the current value of the second constant current source, I C1 is the discharge current of the first capacitor, C A is the capacitance value of the gate parasitic capacitor of the high-side switch, I b is the bias current corresponding to the first bias voltage.

[0033] Optionally, the rising slope of the output voltage of the high-side switch satisfies:

[0034]

[0035] wherein V out is the output voltage of the high-side switch, V A is the gate voltage of the high-side switch, I C1 is the charging current of the first capacitor, C1 is the capacitance value of the first capacitor, I b is the bias current corresponding to the first bias voltage.

[0036] To achieve the above object and other related objects, the present application further provides an electronic product, which at least comprises the slope control circuit of the high-side switch.

[0037] As described above, the slope control circuit of the high-side switch and the electronic product of the present application have the following beneficial effects:

[0038] The slope control circuit of the high-side switch and the electronic product of the present application control the rising slope and the falling slope of the gate voltage of the high-side switch to reach dynamic balance through a negative feedback loop; further, the charging and discharging currents of the first capacitor are equal to the bias current through the configuration of internal devices, thereby realizing the purpose of precisely controlling the rising slope and the falling slope of the gate voltage of the high-side switch through the bias current, so as to improve the electromagnetic compatibility of the circuit in which the high-side switch is located. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 shows a block diagram of the slope control circuit of the high-side switch of the present application.

[0040] Figure 2 shows a specific structural schematic diagram of the slope control circuit of the high-side switch of the present application.

[0041] Figure 3 shows a working principle schematic diagram of the slope control circuit of the high-side switch of the present application.

[0042] ELEMENT NUMBER EXPLANATION

[0043] 1 slope control circuit of high-side switch

[0044] 11 switch module

[0045] 12 detection module

[0046] 121 current detection unit

[0047] 13 operational amplifier

[0048] 14 adjustment module

[0049] 15 bias generation module DETAILED DESCRIPTION

[0050] The present application is herein described, by way of example only, with the application made obvious to those skilled in the art by the teachings and constructions herein disclosed. This application may also be susceptible of embodiment in different forms. There is no intention of limiting the application to the specific form set forth herein. The application is to be limited only by the metes and bounds of the appended claims, appropriately interpreted, along with the rules and principles of patent law.

[0051] Reference will now be made to the drawings, wherein: Figures 1-3 It is to be understood that the drawings are to be used for purposes of illustration only and that the inventive concepts can be applied in any of numerous arrangements, all of which have not necessarily been depicted.

[0052] As shown in Figure 1 , the present application provides a slope control circuit 1 of a high-side switch, which includes:

[0053] a switch module 11, a detection module 12, an operational amplifier 13, a first capacitor C1 and an adjustment module 14.

[0054] As shown in Figure 1 , the switch module 11 adjusts an output voltage by turning on or off the high-side switch.

[0055] Specifically, in the present embodiment, the switch module 11 includes a high-side switch MN SW , a load RL and a first resistor R1. A first end of the high-side switch MN SW is connected to a first power supply voltage VS, a second end is grounded via the load RL, and a control end is connected to the first capacitor C1 and the adjustment module 14; a second end of the high-side switch MN SW serves as an output end OUT. One end of the first resistor R1 is connected to the control end of the high-side switch MN SW , and the other end is connected to the second end of the high-side switch MN SW . As an example, the high-side switch MN SW is implemented by an NMOS transistor, and then the high-side switch MN SWThe first end of the MOSFET is a drain, the second end is a source, and the control end is a gate. The first resistor R1 is a high-side switch MN SW The gate-source resistor of the MOSFET. In actual use, the switch module 11 can be any circuit structure including a high-side switch and controlling the output voltage based on the conduction or turn-off of the high-side switch, and is not limited to the embodiment.

[0056] As shown in Figure 1 , the detection module 12 is connected to the switch module 11, detects the load current of the high-side switch MN SW , and outputs a detection voltage Vsen.

[0057] Specifically, in the embodiment, the detection module 12 includes a current detection unit 121 and a second resistor R2. The first end of the current detection unit 121 is connected to the first power supply voltage VS, the second end is grounded through the second resistor R2, and the third end and the fourth end are respectively connected to the control end and the output end (i.e., the second end of the high-side switch MN SW ) of the high-side switch MN SW ; the second end of the current detection unit 121 outputs the detection voltage Vsen. As an example, the output current of the second end of the current detection unit 121 is proportional to the load current of the high-side switch MN SW , and the output current of the second end of the current detection unit 121 acts on the second resistor R2 to obtain the detection voltage Vsen related to the load current of the high-side switch MN SW . Any circuit structure capable of detecting the load current of the high-side switch MN SW and outputting a corresponding detection voltage is applicable to the present application, and is not limited to the embodiment.

[0058] As shown in Figure 1 , the first input end of the operational amplifier 13 receives the detection voltage Vsen, the second input end receives the reference voltage Vref, and the difference between the two is output as VB.

[0059] Specifically, in the embodiment, the non-inverting input end of the operational amplifier 13 is connected to the detection voltage Vsen, the inverting input end is connected to the reference voltage Vref, and the output end outputs the difference VB; when the detection voltage Vsen is greater than the reference voltage Vref, the difference VB is high; when the detection voltage Vsen is less than the reference voltage Vref, the difference VB is low. The input signal of the operational amplifier 13 and the polarity of the input end can be interchanged, and the polarity of each node can be adjusted by devices such as inverters, and the logic of the present application can be realized, which will not be described here. It should be noted that Vref is an external adjustable reference voltage, and different Vref values can be set according to needs to set the current limiting value of the high-side switch. In the embodiment, the high-side switch works in a non-current limiting state, which satisfies:

[0060] More specifically, as shown in Figure 2 the first PMOS transistor MP1, the second PMOS transistor MP2, the third PMOS transistor MP3, the first NMOS transistor MN1, the second NMOS transistor MN2, the third NMOS transistor MN3, the fourth NMOS transistor MN4, the second capacitor C2 and the third resistor R3. The source of the first PMOS transistor MP1 is connected to the second power supply voltage VDD, the gate is connected to the second bias voltage Vb2, and the drain is connected to the emitter of the first PNP transistor Q1 and the second PNP transistor Q2. The first PNP transistor Q1 and the second PNP transistor Q2 serve as input pair transistors, and the bases thereof serve as the inverting input and the non-inverting input of the operational amplifier 13, respectively. The second PMOS transistor MP2 and the third PMOS transistor MP3 form a current mirror structure, wherein the source of the second PMOS transistor MP2 is connected to the second power supply voltage VDD, and the gate and the drain are connected together; the source of the third PMOS transistor MP3 is connected to the second power supply voltage VDD, and the gate is connected to the gate of the second PMOS transistor MP2. The drain of the first NMOS transistor MN1 is connected to the drain of the second PMOS transistor MP2, the gate receives the third bias voltage Vb3, and the source is connected to the drain of the second NMOS transistor MN2 and the collector of the second PNP transistor Q2; the gate of the second NMOS transistor MN2 receives the fourth bias voltage Vb4, and the source is grounded. The drain of the third NMOS transistor MN3 is connected to the drain of the third PMOS transistor MP3 and serves as the output of the operational amplifier 13, the gate receives the fifth bias voltage Vb5, and the source is connected to the drain of the fourth NMOS transistor MN4 and the collector of the first PNP transistor Q1; the gate of the fourth NMOS transistor MN4 receives the sixth bias voltage Vb6, and the source is grounded. The second capacitor C2 and the third resistor R3 form a series structure, and the two ends of the series structure are connected to the drain of the third NMOS transistor MN3 and the gate of the fourth NMOS transistor MN4, respectively; in this embodiment, one end of the third resistor R3 is connected to the drain of the third NMOS transistor MN3, and the other end is connected to one end of the second capacitor C2; the other end of the second capacitor C2 is connected to the gate of the fourth NMOS transistor MN4. In this embodiment, the third bias voltage Vb3 is equal to the fifth bias voltage Vb5, and the fourth bias voltage Vb4 is equal to the sixth bias voltage Vb6; in actual use, the values of the bias voltages can be set as needed. Any circuit structure capable of obtaining the difference between two input signals is applicable to the present application, and is not limited to this embodiment.

[0061] As shown in Figure 1 one end of the first capacitor C1 is connected to the high-side switch MN SW, the other end is connected to the control end of the first bias voltage Vb1; thus, the first capacitor C1 charging and discharging current can be set by the first bias voltage Vb1, so that the first capacitor C1 charging and discharging current is a constant current related to the first bias voltage Vb1.

[0062] Specifically, in the embodiment, by reasonable configuration of the internal device size, the first capacitor C1 charging and discharging current is equal to the bias current Ib, so as to realize the control of the internal output voltage rising and falling slope based on the bias current.

[0063] As shown in Figure 1 , the adjustment module 14 is connected to the control end of the high-side switch MN SW and the output end of the operational amplifier 13, and receives the switch control signal, controls the high-side switch MN SW to be turned on or turned off based on the switch control signal, and controls the rate of the high-side switch MN SW being turned on or turned off based on the difference value VB and the first capacitor C1 charging and discharging, so as to make the rising or falling slope of the output end voltage of the high-side switch MN SW constant.

[0064] Specifically, in the embodiment, the adjustment module 14 includes a first switch S1, a second switch S2, a first constant current source I1, a second constant current source I2, and an adjustment tube MN A . The first switch S1 is connected in series between the third power supply voltage VCC and the control end of the high-side switch MN SW ; in this example, one end of the first switch S1 is connected to the third power supply voltage VCC, and the other end is connected to the current input end of the first constant current source I1; the current output end of the first constant current source I1 is connected to the control end of the high-side switch MN SW ; when the first switch S1 is controlled to be closed, the first constant current source I1 pulls up the gate voltage of the high-side switch MN SW . The second switch S2 is connected in series between the control end of the high-side switch MN SW and the ground; in this example, one end of the second switch S2 is connected to the control end of the high-side switch MN SW , and the other end is connected to the current input end of the second constant current source I2; the current output end of the second constant current source I2 is grounded; when the second switch S2 is controlled to be closed, the second constant current source I2 pulls down the gate voltage of the high-side switch MN SW . The first end of the adjustment tube MN A is connected to the control end of the high-side switch MN SW , the second end is grounded, and the control end receives the difference value VB; in this example, the adjustment tube MN A is realized by an NMOS tube, so that the first end of the adjustment tube MN A is the drain, the second end is the source, and the control end is the gate.A controlled by the difference VB, for maintaining the high-side switch MN SW The pull-up current of the gate changes at a constant rate. Any high-side switch MN can be maintained based on the detection voltage Vsen SW The structure of the pull-up current and the pull-down current of the gate changing at a constant rate is applicable to the present application, not limited to the present embodiment.

[0065] As shown in Figure 2 The slope control circuit 1 of the high-side switch of the present application further includes a bias generation module 15 for generating the bias voltage (or current) required by the slope control circuit 1 of the high-side switch based on the bias current Ib.

[0066] Specifically, in the embodiment, the bias generation module 15 provides the first bias voltage Vb1, the second bias voltage Vb2, the third bias voltage Vb3, the fourth bias voltage Vb4, the fifth bias voltage Vb5 and the sixth bias voltage Vb6. As an example, the bias generation module 15 includes a fourth PMOS transistor MP4, a fifth PMOS transistor MP5, a sixth PMOS transistor MP6, a fifth NMOS transistor MN5, a sixth NMOS transistor MN6, a seventh NMOS transistor MN7, an eighth NMOS transistor MN8, a fourth resistor R4 and a fifth resistor R5. The source of the fourth PMOS transistor MP4 is connected to the second power supply voltage VDD, the gate and the drain are connected to the bias current Ib and output the second bias voltage Vb2. The source of the fifth PMOS transistor MP5 is connected to the second power supply voltage VDD, the gate is connected to the second bias voltage Vb2, and the drain is connected to the drain of the fifth NMOS transistor MN5 via the fourth resistor R4. The gate of the fifth NMOS transistor MN5 is connected to the drain of the fifth PMOS transistor MP5 and outputs the third bias voltage Vb3. The drain of the sixth NMOS transistor MN6 is connected to the source of the fifth NMOS transistor MN5, the gate is connected to the drain of the fifth NMOS transistor MN5 and outputs the fourth bias voltage Vb4 (in the example, the fourth bias voltage Vb4 is equal to the first bias voltage Vb1, i.e. the fourth bias voltage Vb4 and the first bias voltage Vb1 are obtained from the gate of the sixth NMOS transistor MN6; in actual use, the first bias voltage Vb1 can be set according to the structure of the operational amplifier to connect to a certain bias voltage point inside the operational amplifier to form a negative feedback structure), and the source is grounded. The source of the sixth PMOS transistor MP6 is connected to the second power supply voltage VDD, the gate is connected to the second bias voltage Vb2, and the drain is connected to the drain of the seventh NMOS transistor MN7 via the fifth resistor R5. The gate of the seventh NMOS transistor MN7 is connected to the drain of the sixth PMOS transistor MP6 and outputs the fifth bias voltage Vb5. The drain of the eighth NMOS transistor MN8 is connected to the source of the seventh NMOS transistor MN7, the gate is connected to the drain of the seventh NMOS transistor MN7 and outputs the sixth bias voltage Vb6, and the source is grounded. In actual use, any circuit structure required by the slope control circuit 1 capable of providing a high-side switch based on the bias current Ib is applicable to the present application, and is not limited to the embodiment.

[0067] As Figures 1-3 shown, in the initial state (or high-side switch standby state), the first switch S1 and the second switch S2 are both in the off state, the load current is 0, Vref>Vsen, and the operational amplifier outputs a low level (VB=0). The adjustment tube MN A and the high-side switch MN SW are both in the off state, no current flows into or out of the first capacitor C1 (I C1 =0), and the gate voltage VA of the high-side switch and the output voltage Vout of the slope control circuit 1 of the high-side switch are both 0.

[0068] When the high-side switch is on, the first switch S1 is closed, the second switch S2 is opened, the first current source II charges the gate of the high-side switch MN SW and charges the first capacitor CI, so that the voltage V A at point A rises, and the rate of rise of V A determines the size of the charging current of the first capacitor CI. The negative feedback loop composed of the detection module 12, the operational amplifier 13, the first capacitor CI, and the adjustment tube MN A keeps the rising slope of V A constant. Specifically, when the rising slope of V A increases (is greater than ), the charging current of the first capacitor CI increases, the difference value VB increases, the pull-down capability of the adjustment tube MN A increases, and the voltage at point A rises slowly; when the rising slope of V A decreases (is less than ), the charging current of the first capacitor CI decreases, the difference value VB decreases, the pull-down capability of the adjustment tube MN A decreases, and the voltage at point A rises quickly. Therefore, the negative feedback loop composed of the detection module 12, the operational amplifier 13, the first capacitor CI, and the adjustment tube MN A controls the rising slope of the voltage at the output end OUT of the high-side switch by adjusting the rising slope of the voltage at point A; and the rising slope of the voltage at point A reaches dynamic balance, satisfying: Further, by reasonably configuring the device sizes in the bias generation module 15, it can be ensured that I C1 = II b , and the rising slope of the voltage at point A satisfies: By setting the value of the bias current Ib and the size of the first capacitor CI, the rising slope of the high-side switch can be accurately controlled, and in this example, the rising slope when the high-side switch is on satisfies the electromagnetic compatibility, and in actual use, the rising slope can be set as needed.

[0069] When the high-side switch is off, the second switch S2 is closed, the first switch S1 is opened, the second constant current source I2 discharges the gate of the high-side switch MN SW , and the voltage V A begins to drop, and the current flowing through the first capacitor CI is -I C1 (discharge current). Assuming that the gate parasitic capacitance of the high-side switch MN SW is C A , the voltage drop slope at point A satisfies Further, by ensuring that I C1 = II b , the voltage drop slope at point A satisfies: That is, the falling slope of the high-side switch can be accurately controlled by setting the current value of the second constant current source I2, and in this example, the falling slope when the high-side switch is turned on meets the electromagnetic compatibility, and in actual use, the falling slope can be set as required.

[0070] Further, since the OUT voltage follows the voltage at point A, V OUT The voltage gain of V A Since the voltage gain of V

[0071] The slope control circuit of the high-side switch of the present application can well protect the load device in the case of failure, can improve the efficiency of the mainboard space, save the cost of the system, and provide necessary protection and control for various loads such as motors, lighting, actuators, etc.

[0072] The present application also provides an electronic product, which at least comprises the slope control circuit of the high-side switch of the present application 1. The electronic product is applied to the fields including but not limited to automotive electronics, power management, industrial control, etc.

[0073] In summary, the present application provides a slope control circuit of a high-side switch and an electronic product, which comprises a switch module, a detection module, an operational amplifier, a first capacitor and an adjustment module; the detection module is connected to the switch module, detects the load current of the high-side switch in the switch module, and outputs a detection voltage; the first input end of the operational amplifier receives the detection voltage, the second input end receives a reference voltage, and outputs the difference between the two; one end of the first capacitor is connected to the control end of the high-side switch, and the other end is connected to a first bias voltage; the adjustment module is connected to the control end of the high-side switch and the output end of the operational amplifier, receives a switch control signal, controls the high-side switch to turn on or turn off based on the switch control signal, and controls the rate of turning on or turning off of the high-side switch based on the difference and the charge and discharge of the first capacitor, so as to make the rising or falling slope of the voltage at the output end of the high-side switch constant. The slope control circuit of the high-side switch and the electronic product of the present application control the rising slope and the falling slope of the gate voltage of the high-side switch to reach dynamic balance through a negative feedback loop; further, the rising slope and the falling slope of the gate voltage of the high-side switch are accurately controlled through a bias current, and the electromagnetic compatibility of the circuit in which the high-side switch is located is improved. Therefore, the present application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0074] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. A slope control circuit for a high-side switch, characterized in that, The slope control circuit of the high-side switch includes at least: Switching module, detection module, operational amplifier, first capacitor and adjustment module; The detection module is connected to the switch module, detects the load current of the high-side switch in the switch module, and outputs a detection voltage. The operational amplifier receives the detected voltage at its first input terminal, receives the reference voltage at its second input terminal, and outputs the difference between the two. One end of the first capacitor is connected to the control terminal of the high-side switch, and the other end is connected to the first bias voltage. The adjustment module is connected to the control terminal of the high-side switch and the output terminal of the operational amplifier, and receives the switch control signal. Based on the switch control signal, it controls the high-side switch to turn on or off, and controls the rate at which the high-side switch turns on or off based on the difference and the charging and discharging of the first capacitor, thereby making the rise or fall slope of the output voltage of the high-side switch constant.

2. The slope control circuit for the high-side switch according to claim 1, characterized in that: The switching module includes a high-side switch, a load, and a first resistor; The first terminal of the high-side switch is connected to the first power supply voltage, the second terminal is grounded via the load, and the control terminal is connected to the first capacitor and the adjustment module. One end of the first resistor is connected to the control terminal of the high-side switch, and the other end is connected to the second terminal of the high-side switch.

3. The slope control circuit for the high-side switch according to claim 1, characterized in that: The detection module includes a current detection unit and a second resistor; The first terminal of the current detection unit is connected to the first power supply voltage, the second terminal is grounded through the second resistor, and the third and fourth terminals are respectively connected to the control terminal and the output terminal of the high-side switch; the second terminal of the current detection unit outputs the detection voltage.

4. The slope control circuit for the high-side switch according to claim 1, characterized in that: The operational amplifier's non-inverting input is connected to the detected voltage, its inverting input is connected to the reference voltage, and its output terminal outputs the difference.

5. The slope control circuit for the high-side switch according to claim 1, characterized in that: The operational amplifier includes a first PNP transistor, a second PNP transistor, a first PMOS transistor, a second PMOS transistor, a third PMOS transistor, a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, a fourth NMOS transistor, a second capacitor, and a third resistor; The source of the first PMOS transistor is connected to the second power supply voltage, the gate is connected to the second bias voltage, and the drain is connected to the emitter of the first PNP transistor and the second PNP transistor; the base of the first PNP transistor and the second PNP transistor serve as the inverting input terminal and the non-inverting input terminal of the operational amplifier, respectively. The sources of the second PMOS transistor and the third PMOS transistor are connected to the second power supply voltage, and their gates are connected together and connected to the drain of the second PMOS transistor. The drain of the first NMOS transistor is connected to the drain of the second PMOS transistor, the gate receives a third bias voltage, and the source is connected to the drain of the second NMOS transistor and the collector of the second PNP transistor; the gate of the second NMOS transistor receives a fourth bias voltage, and the source is grounded. The drain of the third NMOS transistor is connected to the drain of the third PMOS transistor and serves as the output terminal of the operational amplifier. Its gate receives a fifth bias voltage, and its source is connected to the drain of the fourth NMOS transistor and the collector of the first PNP transistor. The gate of the fourth NMOS transistor receives a sixth bias voltage, and its source is grounded. The second capacitor and the third resistor form a series structure, with the two ends of the series structure connected to the drain of the third NMOS transistor and the gate of the fourth NMOS transistor, respectively.

6. The slope control circuit for the high-side switch according to claim 5, characterized in that: The third bias voltage is equal to the fifth bias voltage, and the fourth bias voltage is equal to the sixth bias voltage.

7. The slope control circuit for the high-side switch according to claim 1, characterized in that: The adjustment module includes a first switch, a second switch, a first constant current source, a second constant current source, and an adjustment tube; The first switch and the first constant current source are connected in series between the third power supply voltage and the control terminal of the high-side switch; The second switch and the second constant current source are connected in series between the control terminal of the high-side switch and ground; The first end of the adjusting tube is connected to the control terminal of the high-side switch, and the second end is grounded. The control terminal receives the difference value.

8. The slope control circuit for the high-side switch according to claim 7, characterized in that: The slope of the output voltage of the high-side switch decreases in the following way: ； in, The output voltage of the high-side switch is... This refers to the gate voltage of the high-side switch. This represents the current value of the second constant current source. Let be the discharge current of the first capacitor. Let be the capacitance value of the gate parasitic capacitance of the high-side switch. This is the bias current corresponding to the first bias voltage.

9. The slope control circuit for the high-side switch according to claim 1, characterized in that: The rising slope of the output voltage of the high-side switch satisfies: ； in, The output voltage of the high-side switch is... This refers to the gate voltage of the high-side switch. Let be the charging current of the first capacitor. Let be the capacitance value of the first capacitor. This is the bias current corresponding to the first bias voltage.

10. An electronic product, characterized in that, The electronic product includes at least: a slope control circuit for a high-side switch as described in any one of claims 1-9.

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