Slope control circuit of high-side switch and electronic product

Abstract

The invention provides a slope control circuit of a high-side switch and an electronic product, and the circuit comprises a detection module which detects the load current of the high-side switch in a switch module, and outputs a detection voltage; the first input end of the operational amplifier receives the detection voltage, the second input end of the operational amplifier receives the reference voltage, and the difference value is output; one end of the first capacitor is connected with the control end of the high-side switch, and the other end is connected with first bias voltage; and the adjusting module is used for controlling the turning-on or turning-off rate of the high-side switch, so that the rising or falling slope of the voltage at the output end of the high-side switch is constant. According to the slope control circuit of the high-side switch and the electronic product, the grid voltage rising slope and the grid voltage falling slope of the high-side switch are controlled through the negative feedback loop to achieve dynamic balance; furthermore, the rising slope and the falling slope of the grid voltage of the high-side switch are accurately controlled through the bias current, and the electromagnetic compatibility of a circuit where the high-side switch is located is improved.

Description

Technical Field

[0001] The invention 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 Art

[0002] As the clock frequency of modern digital devices using low signal voltages increases rapidly, the issue of electromagnetic compatibility (EMC) becomes increasingly important. Electromagnetic compatibility refers to the ability of a device or system to operate in accordance with requirements in its electromagnetic environment and not generate intolerable electromagnetic disturbance to any device in its environment. That is, it must meet two requirements: on the one hand, the electromagnetic disturbance (EMD) generated by the device to the environment during normal operation must not exceed a certain limit; on the other hand, the device must have a certain degree of immunity to the electromagnetic disturbance in the environment, namely, electromagnetic susceptibility (EMS).

[0003] Among them, the electromagnetic compatibility (EMC) problem of power switches is due to the fact that they generate rapidly changing current and voltage (i.e. dv / dt and di / dt) when they are in high voltage and high current switching state, which leads to strong harmonic interference and spike interference. These interference signals not only affect the normal operation of the circuit where the power switch is located, but may also 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 that technical personnel in this field need to solve urgently.

[0005] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

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

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

[0008] A switch module, a detection module, an operational amplifier, a first capacitor and an 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 terminal of the operational amplifier receives the detection voltage, the second input terminal receives the reference voltage, and outputs the difference between the two;

[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 regulating module is connected to the control end of the high-side switch and the output end of the operational amplifier, and receives a switch control signal, controls the high-side switch to be turned on or off based on the switch control signal, and controls the rate of turning on or off the high-side switch based on the difference and the charging and discharging of the first capacitor, thereby making the rising or falling slope of the output end voltage of the high-side switch constant.

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

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

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

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

[0017] The first end of the current detection unit is connected to the first power supply voltage, the second end is grounded via the second resistor, 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, a non-phase input terminal of the operational amplifier is connected to the detection voltage, an inverting input terminal is connected to the reference voltage, and an output terminal outputs the difference.

[0019] Optionally, 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;

[0020] 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 emitters of the first PNP transistor and the second PNP transistor; the bases 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;

[0021] The sources of the second PMOS tube and the third PMOS tube are connected to the second power supply voltage, and the gates are connected together and connected to the drain of the second PMOS tube;

[0022] 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;

[0023] The drain of the third NMOS tube is connected to the drain of the third PMOS tube and serves as the output end of the operational amplifier, the gate receives the fifth bias voltage, and the source is connected to 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 form a series structure, and two ends of the series structure are respectively connected to 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 regulating module includes 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 supply voltage and a control terminal of the high-side switch;

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

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

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

[0031]

[0032] Among them, 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 of the gate parasitic capacitance 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] Among them, 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 of the first capacitor, I b is the bias current corresponding to the first bias voltage.

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

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

[0038] The slope control circuit and electronic product of the high-side switch of the present invention controls the rising slope and falling slope of the gate voltage of the high-side switch through a negative feedback loop to achieve dynamic balance; further, through the configuration of internal devices, the charging and discharging current of the first capacitor is made equal to the bias current, thereby achieving the purpose of accurately controlling the rising slope and falling slope of the gate voltage of the high-side switch through the bias current, thereby improving the electromagnetic compatibility of the circuit in which the high-side switch is located. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Shown is a block diagram of a slope control circuit of a high-side switch of the present invention.

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

[0041] Figure 3 It is a schematic diagram showing the working principle of the slope control circuit of the high side switch of the present invention.

[0042] Component number description

[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 following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0051] See also Figure 1 to Figure 3 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0052] like Figure 1 As shown, the present invention provides a slope control circuit 1 of a high-side switch, and the slope control circuit of the high-side switch includes:

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

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

[0055] Specifically, in this embodiment, the switch module 11 includes a high-side switch MN SW , load RL and first resistor R1. High side switch MN SW The first end of the high-side switch MN is connected to the first power supply voltage VS, the second end is grounded via the load RL, and the control end is connected to the first capacitor C1 and the regulating module 14; SW The second end of the first resistor R1 is used as the output end OUT. One end of the first resistor R1 is connected to the high-side switch MN SW The other end is connected to the high-side switch MN SW As an example, the high side switch MN SW If NMOS tube is used, the high-side switch MN SWThe first end is the drain, the second end is the source, and the control end is the gate; the first resistor R1 serves as the high-side switch MN SW 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 on or off of the high-side switch, and is not limited to this embodiment.

[0056] like Figure 1 As shown, the detection module 12 is connected to the switch module 11 to detect the high-side switch MN. SW The load current is detected and the detection voltage Vsen is output.

[0057] Specifically, in this 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 via the second resistor R2, and the third end and the fourth end are respectively connected to the high-side switch MN SW The control end and output end (i.e. high-side open tube 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 and the high-side switch MN SW The load current ratio is 1:N, and the output current of the second end of the current detection unit 121 acts on the second resistor R2 to obtain the high-voltage switch MN SW The load current related detection voltage Vsen. SW Any circuit structure that detects the load current and outputs the corresponding detection voltage is applicable to the present invention and is not limited to this embodiment.

[0058] like Figure 1 As shown, the operational amplifier 13 receives a detection voltage Vsen at a first input terminal and a reference voltage Vref at a second input terminal, and outputs a difference VB between the two.

[0059] Specifically, in the present embodiment, the non-inverting input terminal of the operational amplifier 13 is connected to the detection voltage Vsen, the inverting input terminal is connected to the reference voltage Vref, and the output terminal outputs the difference VB; when the detection voltage Vsen is greater than the reference voltage Vref, the difference VB is at a high level; when the detection voltage Vsen is less than the reference voltage Vref, the difference VB is at a low level. The corresponding relationship between the input signal and the polarity of the input terminal of the operational amplifier 13 is interchangeable, and the polarity of each node can be adjusted by devices such as inverters, as long as the logic of the present invention can be implemented, and will not be described one by one here. It should be noted that Vref is an externally adjustable reference voltage, and different Vref values ​​can be set as needed to set the current limiting value of the high-side switch. In the present embodiment, the high-side switch operates in a non-current limiting state, satisfying:

[0060] More specifically, if Figure 2 As shown, as an example, the operational amplifier 13 adopts a folded common source and common gate structure, including a first PNP transistor Q1, a second PNP transistor Q2, a first PMOS transistor MP1, a second PMOS transistor MP2, a third PMOS transistor MP3, a first NMOS transistor MN1, a second NMOS transistor MN2, a third NMOS transistor MN3, a fourth NMOS transistor MN4, a second capacitor C2 and a 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 are used as input pairs, and the bases are used as the inverting input terminal and the non-inverting input terminal 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 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, 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 end of the operational amplifier 13, the gate receives the fifth bias voltage Vb5, 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 respectively connected to the drain of the third NMOS tube MN3 and the gate of the fourth NMOS tube MN4; in this embodiment, one end of the third resistor R3 is connected to the drain of the third NMOS tube 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 tube 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 value of each bias voltage can be set as needed. Any circuit structure that can obtain the difference between two input signals is applicable to the present invention, not limited to this embodiment.

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

[0062] Specifically, in this embodiment, by reasonably configuring the internal device size, the charging and discharging current of the first capacitor C1 is made equal to the bias current Ib, so as to control the rising and falling slopes of the internal output voltage based on the bias current.

[0063] like Figure 1 As shown, the regulating module 14 is connected to the high side switch MN SW and the output end of the operational amplifier 13, and receives a switch control signal, and controls the high-side switch MN based on the switch control signal SW Turn on or off, and control the high-side switch MN based on the difference VB and the charge and discharge of the first capacitor C1 SW The rate of turning on or off, thus making the high-side switch MN SW The rising or falling slope of the output voltage is constant.

[0064] Specifically, in this embodiment, the regulating 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 adjusting transistor MN. A The first switch S1 and the first constant current source I1 are connected in series to the third power supply voltage VCC and 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 high-side switch MN SW When the first switch S1 is controlled to close, the first constant current source I1 pulls up the high-side switch MN SW The second switch S2 and the second constant current source I2 are connected in series to the high-side switch MN SW In this example, one end of the second switch S2 is connected to the high-side switch MN SW 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 close, the second constant current source I2 pulls down the high-side switch MN SW The gate voltage of the adjustment tube MN A The first end is connected to the high side switch MN SW The control end of the adjustment tube MN is connected to the ground, and the control end receives the difference VB. In this example, the adjustment tube MN A If NMOS tube is used, then the adjustment tube MN A The first end is the drain, the second end is the source, and the control end is the gate; the adjustment tube MNA Controlled by the difference VB, used to maintain the high-side switch MN SW The gate pull-up current changes at a constant rate. Any gate pull-up current that can maintain the high-side switch MN based on the detection voltage Vsen SW The structures in which the change rates of the gate pull-up current and the pull-down current are constant are applicable to the present invention and are not limited to this embodiment.

[0065] like Figure 2 As shown, the slope control circuit 1 of the high side switch of the present invention further includes a bias generating module 15 for generating a 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 this embodiment, the bias generation module 15 provides a first bias voltage Vb1, a second bias voltage Vb2, a third bias voltage Vb3, a fourth bias voltage Vb4, a fifth bias voltage Vb5 and a 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 tube MN6 is connected to the source of the fifth NMOS tube MN5, the gate is connected to the drain of the fifth NMOS tube MN5 and outputs the fourth bias voltage Vb4 (in this example, the fourth bias voltage Vb4 is equal to the first bias voltage Vb1, that is, the fourth bias voltage Vb4 and the first bias voltage Vb1 are obtained from the gate of the sixth NMOS tube MN6; in actual use, the first bias voltage vb1 connected to a certain bias voltage point inside the operational amplifier can be set according to the structure of the operational amplifier to form a negative feedback structure), and the source is grounded. The source of the sixth PMOS tube 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 tube MN7 via the fifth resistor R5. The gate of the seventh NMOS tube MN7 is connected to the drain of the sixth PMOS tube 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 that can provide the required bias of the slope control circuit 1 of the high-side switch based on the bias current Ib is applicable to the present invention, and is not limited to this embodiment.

[0067] like Figure 1 to Figure 3 As shown, in the initial state (or the 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, then the operational amplifier output is low level (VB=0), and the adjustment tube MN A And high side switch MN SW are both in the cut-off state, and no current flows into or out of the first capacitor C1 (I C1 =0), 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 turned on, the first switch S1 is closed and the second switch S2 is opened, and the first current source I1 is applied to the high-side switch MN. SW The gate of the capacitor C1 is charged, so that the voltage V A Rise, V A The rising rate determines the size of the charging current of the first capacitor C1, which is controlled by the detection module 12, the operational amplifier 13, the first capacitor C1 and the adjustment tube MN. A The negative feedback loop makes V A The rising slope of V A The rising slope increases (greater than ), the charging current of the first capacitor C1 increases, the difference VB increases, and the adjustment tube MN A The pull-down capability is enhanced, and the voltage rise at point A becomes slower; when V A The rising slope decreases (less than ), the charging current of the first capacitor C1 decreases, the difference VB decreases, and the adjustment tube MN A The pull-down capability is weakened, and the voltage at point A rises faster. Therefore, during the high-side switch on process, the detection module 12, the operational amplifier 13, the first capacitor C1 and the adjustment tube MN A The negative feedback loop formed by adjusting the rising slope of the voltage at point A controls the rising slope of the voltage at the output terminal OUT of the high-side switch; and the rising slope of the voltage at point A reaches a dynamic balance, satisfying: Furthermore, by properly configuring the device size in the bias generating module 15, I C1 =I b , then, the voltage rising slope at point A satisfies: By setting the value of the bias current Ib and the size of the first capacitor C1, the rising slope of the high-side switch can be accurately controlled. In this example, the rising slope when the high-side switch is turned on meets electromagnetic compatibility. In actual use, the rising slope can be set as needed.

[0069] When the high-side switch is turned off, the second switch S2 is closed and the first switch S1 is opened, and the second constant current source I2 is connected to the high-side switch MN. SW The gate discharges and makes its voltage V A The current flowing through the first capacitor C1 is -I C1 (discharge current), assuming that the high-side switch MN SW The gate parasitic capacitance is C A , the voltage drop slope at point A satisfies Further, I C1 =I b , then, 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. In this example, the falling slope when the high-side switch is turned on meets electromagnetic compatibility. In actual use, the falling slope can be set as needed.

[0070] Furthermore, since the OUT voltage follows the voltage at point A, V OUT V A The voltage gain is approximately 1, so the rising and falling rates of the voltage at the OUT terminal are equal to the rising and falling rates of the voltage at point A.

[0071] The slope control circuit of the high-side switch of the present invention can well protect the load equipment in the event of a fault, 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, and transmissions.

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

[0073] In summary, the present invention provides a slope control circuit and electronic product of a high-side switch, including: 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 the 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 the 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, and receives a switch control signal, controls the high-side switch to turn on or off based on the switch control signal, and controls the rate of turning on or off the high-side switch based on the difference and the charging and discharging of the first capacitor, thereby making the rising or falling slope of the output end voltage of the high-side switch constant. The slope control circuit and electronic product of the high-side switch of the present invention control the rising slope and falling slope of the gate voltage of the high-side switch through a negative feedback loop to achieve dynamic balance; further, the rising slope and falling slope of the gate voltage of the high-side switch are accurately controlled through the bias current, thereby improving the electromagnetic compatibility of the circuit where the high-side switch is located. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0074] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A slope control circuit for a high-side switch, characterized in that: The slope control circuit of the high-side switch at least 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 terminal of the operational amplifier receives the detection voltage, the second input terminal receives the 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 regulating module is connected to the control end of the high-side switch and the output end of the operational amplifier, and receives a switch control signal, controls the high-side switch to be turned on or off based on the switch control signal, and controls the rate of turning on or off the high-side switch based on the difference and the charging and discharging of the first capacitor, thereby making the rising or falling slope of the output end voltage of the high-side switch constant.

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

3. The slope control circuit of 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 end of the current detection unit is connected to the first power supply voltage, the second end is grounded via the second resistor, 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.

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

5. The slope control circuit of 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 emitters of the first PNP transistor and the second PNP transistor; the bases 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 tube and the third PMOS tube are connected to the second power supply voltage, and the gates are connected together and connected to the drain of the second PMOS tube; 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 tube is connected to the drain of the third PMOS tube and serves as the output end of the operational amplifier, the gate receives the fifth bias voltage, and the source is connected to 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; The second capacitor and the third resistor form a series structure, and two ends of the series structure are respectively connected to the drain of the third NMOS tube and the gate of the fourth NMOS tube.

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

8. The slope control circuit of the high side switch according to claim 7, characterized in that: The falling slope of the output voltage of the high-side switch satisfies: Among them, V out is the output voltage of the high-side switch, V A 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 of the gate parasitic capacitance of the high-side switch, I b is the bias current corresponding to the first bias voltage.

9. The slope control circuit of a high side switch according to claim 1, characterized in that: The rising slope of the output voltage of the high-side switch satisfies: Among them, 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 of the first capacitor, I b is the bias current corresponding to the first bias voltage.

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

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