Control circuit and driving module

Abstract

The utility model discloses a control circuit and a driving module, the control circuit comprises a first amplification unit, a first filtering unit and a second amplification unit, the first amplification unit is connected with a reference voltage to amplify the reference voltage and generate a first voltage; the first filtering unit is connected with the first amplifying unit to filter the first voltage and generate a second voltage, a first input end of the second amplifying unit is connected with the first filtering unit to receive the second voltage, and a second input end of the second amplifying unit is used for receiving a first feedback voltage generated by the driving circuit; the output end of the second amplification unit is connected with the driving circuit. The second amplification unit is used for generating control voltage used for controlling the driving circuit based on the second voltage and the first feedback voltage. According to the control circuit and the driving module, the amplifier and the first filtering unit are arranged, so that the rising speed of the reference voltage can be inhibited, the rising speed of the output voltage is controlled to be slowed down, and overshoot of the output voltage is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of driving circuits, and particularly relates to a control circuit and a driving module. Background Art

[0002] In many power chips, a control unit is used to control a driving circuit to generate a required output voltage based on a reference voltage and a feedback voltage. If the voltage rising speed of the reference voltage is too fast when powered on, the output voltage will rise rapidly accordingly, and overshoot is likely to occur. The current solution is to connect a capacitor to the PIN foot receiving the reference voltage, but this will also limit the rising speed of the reference voltage, resulting in a greatly extended rising time and an overly long response time of the driving circuit.

[0003] The information disclosed in this background art section is only intended to enhance the overall understanding of the utility model and should not be regarded as an admission or any form of suggestion that this information constitutes prior art already known to those of ordinary skill in the art. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a control circuit and a driving module, which can solve the problem that the driving voltage generated by the driving circuit is overshot due to the too-fast rising of the reference voltage.

[0005] To achieve the above purpose, a specific embodiment of the utility model provides a control circuit for controlling a driving circuit, characterized in that the control circuit includes a first amplification unit, a first filtering unit, and a second amplification unit. The first amplification unit is connected to the reference voltage to amplify the reference voltage and generate a first voltage. The first filtering unit is connected to the first amplification unit to filter the first voltage and generate a second voltage. The first input terminal of the second amplification unit is connected to the first filtering unit to receive the second voltage. The second input terminal of the second amplification unit is used to receive a first feedback voltage generated by the driving circuit. The output terminal of the second amplification unit is connected to the driving circuit. The second amplification unit is used to generate a control voltage for controlling the driving circuit based on the second voltage and the first feedback voltage.

[0006] In one or more embodiments of the utility model, the first amplification unit includes an amplifier, a first driving transistor, and a first feedback unit. The first input terminal of the amplifier is connected to the reference voltage. The control terminal of the first driving transistor is connected to the output terminal of the amplifier. The first terminal of the first driving transistor is connected to the power supply voltage. The second terminal of the first driving transistor is connected to the first feedback unit and the first filtering unit to generate a first voltage. The first feedback unit is connected to the second input terminal of the amplifier to generate a second feedback voltage based on the first voltage.

[0007] In one or more embodiments of the present utility model, the amplifier includes a first current source, a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, and an eighth transistor; a first end of the first current source is connected to a power supply voltage, a second end of the first current source is connected to a first end of the first transistor and a first end of the second transistor, a control end of the first transistor is used to form a first input end of the amplifier, a control end of the second transistor is used to form a second input end of the amplifier, a second end of the first transistor is connected to a second end of the third transistor, a control end of the third transistor, and a control end of the fourth transistor, a first end of the third transistor and a first end of the fourth transistor are connected to a ground voltage, a second end of the fourth transistor is connected to a second end of the seventh transistor, a control end of the seventh transistor, and a control end of the eighth transistor, a first end of the seventh transistor and a first end of the eighth transistor are connected to the power supply voltage; a second end of the second transistor is connected to a second end of the fifth transistor, a control end of the fifth transistor, and a control end of the sixth transistor, a first end of the fifth transistor and a first end of the sixth transistor are connected to the ground voltage, and a second end of the sixth transistor is connected to a second end of the eighth transistor and forms an output end of the amplifier.

[0008] In one or more embodiments of the present utility model, the first feedback unit includes a first resistor and a second resistor, a first end of the first resistor is connected to a second end of the driving transistor and the filtering unit, a second end of the first resistor and a first end of the second resistor are connected to a second input end of the first amplifier, and a second end of the second resistor is connected to the ground voltage.

[0009] In one or more embodiments of the present utility model, the first filtering unit includes a third resistor and a first capacitor, a first end of the third resistor is connected to the first amplifying unit, a second end of the third resistor and a first end of the first capacitor are connected to the second amplifying unit, and a second end of the first capacitor is connected to the ground voltage.

[0010] A specific embodiment of the present utility model further provides a driving module, including the above control circuit and driving circuit, the driving circuit includes a driving unit and a second feedback unit, the driving unit is connected to the control circuit to generate a driving voltage based on the control of the control voltage, and the second feedback unit is connected to the driving unit to generate a first feedback voltage based on the driving voltage.

[0011] In one or more embodiments of the present utility model, the driving unit includes a control unit, a second driving tube, and a third driving tube. The control unit is connected to a control circuit, the control ends of the second driving tube and the third driving tube. The control unit is configured to control the on / off states of the second driving tube and the third driving tube based on a control voltage. The first end of the second driving tube is connected to a power supply voltage. The second ends of the second driving tube and the third driving tube are connected to a second feedback unit to generate a driving voltage. The first end of the third driving tube is connected to a ground voltage.

[0012] In one or more embodiments of the present utility model, the second feedback unit includes a fourth resistor and a fifth resistor. The first end of the fourth resistor is connected to the driving unit. The second end of the fourth resistor is connected to the first end of the fifth resistor to generate a first feedback voltage. The second end of the fifth resistor is connected to a ground voltage.

[0013] In one or more embodiments of the present utility model, the driving circuit further includes a second filtering unit connected to the driving unit and the second feedback unit. The second filtering unit is configured to filter the driving voltage.

[0014] In one or more embodiments of the present utility model, the second filtering unit includes an inductor and a second capacitor. The first end of the inductor is connected to the driving unit. The second end of the inductor and the first end of the second capacitor are connected to the second feedback unit. The second end of the second capacitor is connected to a ground voltage.

[0015] Compared with the prior art, the control circuit and the driving module of the present utility model can suppress the rising speed of the reference voltage by setting an amplifier and a first filtering unit, thereby controlling the output voltage to rise more slowly and avoiding overshoot of the output voltage. This solution can also be applied to various scenarios where the output voltage needs to rise slowly, can provide stable time control, and can stably control the output voltage regardless of the level or change speed of the reference voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments described in the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is the circuit schematic diagram of the control circuit in an embodiment of the present utility model.

[0018] Figure 2 It is the circuit schematic diagram of the driving module in an embodiment of the present utility model. Detailed implementation manners

[0019] In order to enable those skilled in the art to better understand the technical solutions in the present utility model, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0020] In the specification, "coupled", "connected", or "linked" includes both direct connection and indirect connection. Indirect connection is a connection through an intermediate medium, such as a connection through an electrical conduction medium, which may have a parasitic inductance L1 or a parasitic capacitance; the indirect connection may also include a connection through other active devices or passive devices on the basis of achieving the same or similar functional purposes, such as a connection through circuits or components such as switches and follower circuits. In addition, in the present utility model, words such as "first" and "second" are mainly used to distinguish one technical feature from another technical feature, and do not necessarily require or imply that there is a certain actual relationship, quantity, or order between these technical features.

[0021] As Figure 1 shown, a control circuit in an embodiment of the present utility model includes a first amplification unit 10, a first filtering unit, and a second amplification unit 20. The control circuit is used to control a drive circuit.

[0022] Among them, the first amplification unit 10 is connected to a reference voltage VREF to amplify the reference voltage VREF and generate a first voltage V1. The first filtering unit is connected to the first amplification unit 10 to filter the first voltage V1 and generate a second voltage V2. The first input terminal of the second amplification unit 20 is connected to the first filtering unit to receive the second voltage V2. The second input terminal of the second amplification unit 20 is used to receive a first feedback voltage VFB generated by the drive circuit. The output terminal of the second amplification unit 20 is connected to the drive circuit. The second amplification unit 20 is used to generate a control voltage VCT for controlling the drive circuit based on the second voltage V2 and the first feedback voltage VFB.

[0023] The first amplification unit 10 includes an amplifier, a first driving transistor P1, and a first feedback unit. The first input terminal of the amplifier is connected to the reference voltage VREF. The control terminal of the first driving transistor P1 is connected to the output terminal of the amplifier. The first terminal of the first driving transistor P1 is connected to the power supply voltage VDD. The second terminal of the first driving transistor P1 is connected to the first feedback unit and the first filtering unit to generate a first voltage V1. The first feedback unit is connected to the second input terminal of the amplifier to generate a second feedback voltage VF1 based on the first voltage V1.

[0024] In one embodiment, the amplifier includes a first current source I1, a first transistor M1, a second transistor M2, a third transistor M3, a fourth transistor M4, a fifth transistor M5, a sixth transistor M6, a seventh transistor M7, and an eighth transistor M8.

[0025] The first terminal of the first current source I1 is connected to the power supply voltage VDD. The second terminal of the first current source I1 is connected to the first terminal of the first transistor M1 and the first terminal of the second transistor M2. The control terminal of the first transistor M1 is used to form the first input terminal of the amplifier. The control terminal of the second transistor M2 is used to form the second input terminal of the amplifier. The second terminal of the first transistor M1 is connected to the second terminal of the third transistor M3, the control terminal of the third transistor M3, and the control terminal of the fourth transistor M4. The first terminal of the third transistor M3 and the first terminal of the fourth transistor M4 are connected to the ground voltage. The second terminal of the fourth transistor M4 is connected to the second terminal of the seventh transistor M7, the control terminal of the seventh transistor M7, and the control terminal of the eighth transistor M8. The first terminal of the seventh transistor M7 and the first terminal of the eighth transistor M8 are connected to the power supply voltage VDD.

[0026] The second terminal of the second transistor M2 is connected to the second terminal of the fifth transistor M5, the control terminal of the fifth transistor M5, and the control terminal of the sixth transistor M6. The first terminal of the fifth transistor M5 and the first terminal of the sixth transistor M6 are connected to the ground voltage. The second terminal of the sixth transistor M6 is connected to the second terminal of the eighth transistor M8 and forms the output terminal of the amplifier.

[0027] In other embodiments, the amplifier may also adopt other forms of amplifier circuits.

[0028] As Figure 1 shown, the first feedback unit includes a first resistor R1 and a second resistor R2. The first terminal of the first resistor R1 is connected to the second terminal of the driving transistor and the filtering unit. The second terminal of the first resistor R1 and the first terminal of the second resistor R2 are connected to the control terminal of the second transistor M2. The second terminal of the second resistor R2 is connected to the ground voltage.

[0029] As Figure 1As shown, the first filtering unit includes a third resistor R3 and a first capacitor C1. The first end of the third resistor R3 is connected to the first amplifying unit 10. The second end of the third resistor R3 and the first end of the first capacitor C1 are connected to the second amplifying unit 20. The second end of the first capacitor C1 is connected to the ground voltage.

[0030] In one embodiment, the second amplifying unit 20 includes a second current source I2, a ninth transistor M9, a tenth transistor M10, an eleventh transistor M11, a twelfth transistor M12, a thirteenth transistor M13, a fourteenth transistor M14, a fifteenth transistor M15, and a sixteenth transistor M16.

[0031] The first end of the second current source I2 is connected to the power supply voltage VDD. The second end of the second current source I2 is connected to the first end of the ninth transistor M9 and the first end of the tenth transistor M10. The control end of the ninth transistor M9 is used to form the first input terminal of the second amplifying unit 20. The control end of the tenth transistor M10 is used to form the second input terminal of the second amplifying unit 20. The second end of the ninth transistor M9 is connected to the second end of the eleventh transistor M11, the control end of the eleventh transistor M11, and the control end of the twelfth transistor M12. The first end of the eleventh transistor M11 and the first end of the twelfth transistor M12 are connected to the ground voltage. The second end of the twelfth transistor M12 is connected to the second end of the fifteenth transistor M15, the control end of the fifteenth transistor M15, and the control end of the sixteenth transistor M16. The first end of the fifteenth transistor M15 and the first end of the sixteenth transistor M16 are connected to the power supply voltage VDD.

[0032] The second end of the tenth transistor M10 is connected to the second end of the thirteenth transistor M13, the control end of the thirteenth transistor M13, and the control end of the fourteenth transistor M14. The first end of the thirteenth transistor M13 and the first end of the fourteenth transistor M14 are connected to the ground voltage. The second end of the fourteenth transistor M14 is connected to the second end of the sixteenth transistor M16 to form the output terminal of the second amplifying unit 20 and generate a control voltage VCT.

[0033] In other embodiments, the second amplifying unit 20 may also adopt other forms of amplifying circuits.

[0034] When the reference voltage VREF changes, the first voltage V1 will be stabilized at the reference voltage VREF. However, when the reference voltage VREF changes too fast, such as during a rapid power-on, while the first voltage V1 is being stabilized, an overshoot will also occur. A small spike will first appear on its waveform and then return to the same voltage value as the reference voltage VREF. Through the RC filtering circuit composed of the third resistor R3 and the first capacitor C1, this spike can be effectively filtered out, so that the second voltage V2 will finally show a slower rise to the value of the reference voltage VREF.

[0035] After the second amplification unit 20 receives the change in the second voltage V2, the control voltage VCT also changes relatively slowly following the second voltage V2. During the process that the driving circuit adjusts the driving voltage VOUT according to the control voltage VCT, there will be no overshoot phenomenon caused by the too fast rising speed of the control voltage VCT or the overshoot problem of the control voltage VCT itself.

[0036] By adjusting the parameters of the third resistor R3 and the first capacitor C1, the regulation of the change speed of the second voltage V2 can be achieved. At the same time, compared with the way of directly adding a capacitor in the prior art, the change rate of the second voltage V2 in this solution is faster, so that the circuit response time will not be too long. This solution can also be applied to various scenarios where the output voltage needs to rise slowly, can provide stable time control, and can stably control the output voltage regardless of the level or change speed of the reference voltage VREF.

[0037] In one embodiment, the first transistor M1, the second transistor M2, the seventh transistor M7, the eighth transistor M8, the ninth transistor M9, the tenth transistor M10, the fifteenth transistor M15, the sixteenth transistor M16, and the first driving transistor P1 are P-channel transistors. The third transistor M3, the fourth transistor M4, the fifth transistor M5, the sixth transistor M6, the eleventh transistor M11, the twelfth transistor M12, the thirteenth transistor M13, and the fourteenth transistor M14 are N-channel transistors.

[0038] Among the first transistor M1, the second transistor M2, the third transistor M3, the fourth transistor M4, the fifth transistor M5, the sixth transistor M6, the seventh transistor M7, the eighth transistor M8, the ninth transistor M9, the tenth transistor M10, the eleventh transistor M11, the twelfth transistor M12, the thirteenth transistor M13, the fourteenth transistor M14, the fifteenth transistor M15, the sixteenth transistor M16, and the first driving transistor P1, their first ends are all source electrodes, the second ends are all drain electrodes, and the control ends are all gate electrodes.

[0039] In other embodiments, the first transistor M1, the second transistor M2, the seventh transistor M7, the eighth transistor M8, the ninth transistor M9, the tenth transistor M10, the fifteenth transistor M15, the sixteenth transistor M16, and the first driving transistor P1 can also be N-channel transistors or other types of devices. The third transistor M3, the fourth transistor M4, the fifth transistor M5, the sixth transistor M6, the eleventh transistor M11, the twelfth transistor M12, the thirteenth transistor M13, and the fourteenth transistor M14 can also be P-channel transistors or other types of devices, and their connection manners are all adjusted adaptively.

[0040] Such as Figure 2As shown in the figure, the present embodiment further provides a driving module, which includes the above control circuit and driving circuit. The driving circuit includes a driving unit and a second feedback unit. The driving unit is connected to the control circuit to generate a driving voltage VOUT based on the control of the control voltage VCT, and the second feedback unit is connected to the driving unit to generate a first feedback voltage VFB based on the driving voltage VOUT.

[0041] Specifically, the driving unit includes a control unit 30, a second driving transistor P2, and a third driving transistor P3. The control unit 30 is connected to the control circuit, the control terminals of the second driving transistor P2 and the third driving transistor P3. The control unit 30 is used to control the on and off of the second driving transistor P2 and the third driving transistor P3 based on the control voltage VCT. The first end of the second driving transistor P2 is connected to the power supply voltage VDD, the second end of the second driving transistor P2 and the second end of the third driving transistor P3 are connected to the second feedback unit to generate the driving voltage VOUT, and the first end of the third driving transistor P3 is connected to the ground voltage.

[0042] The second feedback unit includes a fourth resistor R4 and a fifth resistor R5. The first end of the fourth resistor R4 is connected to the driving unit, the second end of the fourth resistor R4 is connected to the first end of the fifth resistor R5 to generate the first feedback voltage VFB, and the second end of the fifth resistor R5 is connected to the ground voltage.

[0043] In one embodiment, the driving circuit further includes a second filtering unit connected to the driving unit and the second feedback unit. The second filtering unit is used to filter the driving voltage VOUT.

[0044] The second filtering unit includes an inductor L1 and a second capacitor C2. The first end of the inductor L1 is connected to the driving unit, the second end of the inductor L1 and the first end of the second capacitor C2 are connected to the second feedback unit, and the second end of the second capacitor C2 is connected to the ground voltage.

[0045] In other embodiments, the second filtering unit may not be provided either.

[0046] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0047] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only includes an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A control circuit for controlling a drive circuit, characterized in that: The control circuit includes a first amplifier unit, a first filtering unit and a second amplifier unit. The first amplifier unit is connected to a reference voltage to amplify the reference voltage and generate a first voltage. The first filtering unit is connected to the first amplifier unit to filter the first voltage and generate a second voltage. The first input end of the second amplifier unit is connected to the first filtering unit to receive the second voltage. The second input end of the second amplifier unit is used to receive a first feedback voltage generated by a driving circuit. The output end of the second amplifier unit is connected to the driving circuit. The second amplifier unit is used to generate a control voltage for controlling the driving circuit based on the second voltage and the first feedback voltage.

2. The control circuit according to claim 1, characterized in that: The first amplification unit includes an amplifier, a first driving tube and a first feedback unit, the first input end of the amplifier is connected to a reference voltage, the control end of the first driving tube is connected to the output end of the amplifier, the first end of the first driving tube is connected to a power supply voltage, the second end of the first driving tube is connected to the first feedback unit and the first filtering unit to generate a first voltage, and the first feedback unit is connected to the second input end of the amplifier to generate a second feedback voltage based on the first voltage.

3. The control circuit according to claim 2, characterized in that: The amplifier includes a first current source, a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, and an eighth transistor; The first end of the first current source is connected to the power supply voltage, the second end of the first current source is connected to the first end of the first transistor and the first end of the second transistor, the control end of the first transistor is used to form the first input end of the amplifier, the control end of the second transistor is used to form the second input end of the amplifier, the second end of the first transistor is connected to the second end of the third transistor, the control end of the third transistor, and the control end of the fourth transistor, the first end of the third transistor and the first end of the fourth transistor are connected to the ground voltage, the second end of the fourth transistor is connected to the second end of the seventh transistor, the control end of the seventh transistor, and the control end of the eighth transistor, and the first end of the seventh transistor and the first end of the eighth transistor are connected to the power supply voltage; The second end of the second transistor is connected to the second end of the fifth transistor, the control end of the fifth transistor, and the control end of the sixth transistor. The first end of the fifth transistor and the first end of the sixth transistor are connected to the ground voltage. The second end of the sixth transistor is connected to the second end of the eighth transistor and forms the output end of the amplifier.

4. The control circuit according to claim 2, characterized in that: The first feedback unit includes a first resistor and a second resistor, the first end of the first resistor is connected to the second end of the driving tube and the filtering unit, the second end of the first resistor and the first end of the second resistor are connected to the second input end of the first amplifier, and the second end of the second resistor is connected to the ground voltage.

5. The control circuit according to claim 1, characterized in that: The first filtering unit includes a third resistor and a first capacitor, the first end of the third resistor is connected to the first amplifying unit, the second end of the third resistor and the first end of the first capacitor are connected to the second amplifying unit, and the second end of the first capacitor is connected to the ground voltage.

6. A driving module, characterized in that: It includes the control circuit and driving circuit described in any one of claims 1 to 5, the driving circuit includes a driving unit and a second feedback unit, the driving unit is connected to the control circuit to generate a driving voltage based on the control of the control voltage, and the second feedback unit is connected to the driving unit to generate a first feedback voltage based on the driving voltage.

7. The driving module according to claim 6, characterized in that: The driving unit includes a control unit, a second driving tube and a third driving tube. The control unit is connected to the control circuit, the control end of the second driving tube and the control end of the third driving tube. The control unit is used to control the on and off of the second driving tube and the third driving tube based on the control voltage. The first end of the second driving tube is connected to the power supply voltage, the second end of the second driving tube and the second end of the third driving tube are connected to the second feedback unit to generate a driving voltage, and the first end of the third driving tube is connected to the ground voltage.

8. The driving module according to claim 6, characterized in that: The second feedback unit includes a fourth resistor and a fifth resistor, a first end of the fourth resistor is connected to the driving unit, a second end of the fourth resistor is connected to a first end of the fifth resistor to generate a first feedback voltage, and a second end of the fifth resistor is connected to a ground voltage.

9. The driving module according to claim 7, characterized in that: The driving circuit further includes a second filtering unit connected to the driving unit and the second feedback unit, and the second filtering unit is used for filtering the driving voltage.

10. The driving module according to claim 9, characterized in that: The second filtering unit includes an inductor and a second capacitor, a first end of the inductor is connected to the driving unit, a second end of the inductor and a first end of the second capacitor are connected to the second feedback unit, and a second end of the second capacitor is connected to the ground voltage.

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