Negative voltage output circuit and self-adaptive discharge circuit thereof

Abstract

The invention relates to a negative voltage output circuit and an adaptive discharge circuit thereof. The self-adaptive discharging circuit comprises a discharging module, a control module and an enabling module, the control module is connected with the discharging module and the enabling module, and the discharging module is connected with a grounding end and the negative voltage output end of the negative voltage output circuit. Wherein the discharge module is used for discharging the output voltage of the negative voltage output end to the grounding end; the control module is used for outputting a control signal of the discharge module; the discharge module is controlled to work through the control signal; the enabling module is used for forbidding the control module to output a control signal when the negative voltage output circuit is in a working state; and when the negative voltage output circuit is not in the working state, the enabling control module outputs a control signal. Therefore, when the power supply voltage of the negative voltage output circuit and the enable control signal are cancelled at the same time, the output voltage of the negative voltage output end is released to the grounding end, and damage to related devices can be avoided.

Description

Technical Field

[0001] This disclosure relates to the field of electronic circuit technology, and more specifically, to a negative voltage output circuit and its adaptive discharge circuit. Background Technology

[0002] In related technologies, for some negative voltage output circuits, such as negative voltage output charge pump circuits and buck-boost circuits, the circuit stops working when shut down, and the output voltage discharges to ground. Traditional discharge circuits connect the output to ground via logic control circuits to achieve discharge. However, if both the supply voltage and the enable control signal are simultaneously removed, the logic control circuit loses its logic, and the output will be in a floating state. The output voltage will not be discharged in a short time, potentially damaging related components. Summary of the Invention

[0003] The main purpose of this disclosure is to provide a negative voltage output circuit and its adaptive discharge circuit to solve the technical problem that if the power supply voltage and the enable control signal are simultaneously removed, the related devices will be damaged. The disclosure achieves the technical effect of discharging the output voltage of the negative voltage output terminal to the ground terminal when the power supply voltage and the enable control signal of the negative voltage output circuit are simultaneously removed, thereby avoiding damage to the related devices.

[0004] To achieve the above objectives, a first aspect of this disclosure proposes an adaptive discharge circuit, which includes a discharge module, a control module, and an enable module. The control module is connected to both the discharge module and the enable module, and the discharge module is connected to both a ground terminal and the negative voltage output terminal of the negative voltage output circuit. The discharge module is used to discharge the output voltage from the negative voltage output terminal to the ground terminal; The control module is used to output control signals to the discharge module; the control signals are used to control the operation of the discharge module. The enable module is used to disable the control module from outputting control signals when the negative pressure output circuit is in operation, and to enable the control module to output control signals when the negative pressure output circuit is not in operation.

[0005] In some possible implementations, the control module includes a first resistor, a second resistor, a third resistor, a first field-effect transistor, a second field-effect transistor, a current mirror structure, a capacitor, and a diode, wherein the current mirror structure includes a third field-effect transistor and a fourth field-effect transistor. The first terminal of the first field-effect transistor is connected to the enable module, the second terminal is connected to the power supply terminal of the negative voltage output circuit through the second resistor, and the third terminal is connected to the third terminal of the fourth field-effect transistor. The first end of the second field-effect transistor is connected to the second end of the third field-effect transistor, the second end is connected to the discharge module, and the third end is connected to the second end of the fourth field-effect transistor. The first terminal of the third field-effect transistor is connected to the first terminal of the fourth field-effect transistor, the second terminal is connected to the discharge module through the third resistor, and the third terminal is connected to the ground terminal through the first resistor. Short-circuit the first and third terminals of the fourth field-effect transistor; The first terminal of the capacitor is connected to the third terminal of the first field-effect transistor, and the second terminal is connected to the discharge module. The first end of the diode is connected to the third end of the first field-effect transistor, and the second end is connected to the discharge module.

[0006] In some possible implementations, the enable module includes a current source, a fifth resistor, a fifth field-effect transistor, a sixth field-effect transistor, a seventh field-effect transistor, and an eighth field-effect transistor; The first and third terminals of the fifth field-effect transistor are shorted. The first terminal of the fifth field-effect transistor is connected to the first terminal of the sixth field-effect transistor. The second terminal is connected to the power supply terminal of the negative voltage output circuit. The third terminal is connected to the ground terminal through a current source. The second terminal of the sixth field-effect transistor is connected to the power supply terminal of the negative voltage output circuit, and the third terminal is connected to the second terminal of the seventh field-effect transistor. The first terminal of the seventh field-effect transistor is connected to the enable signal terminal, and the third terminal is connected to the control module through the fifth resistor. The first terminal of the eighth field-effect transistor is connected to the third terminal of the seventh field-effect transistor, the second terminal is connected to the negative voltage output terminal, and the third terminal is connected to the control module.

[0007] In some possible implementations, the enable module may further include a first inverter and a second inverter; The first terminal of the seventh field-effect transistor is connected to the enable signal terminal through the first inverter and the second inverter.

[0008] In some possible implementations, the discharge module includes a ninth field-effect transistor; The first terminal of the ninth MOSFET is connected to the control module, the second terminal is connected to the negative voltage output terminal, and the third terminal is connected to the ground terminal.

[0009] In some possible implementations, The control module is specifically used to output the gate control voltage of the ninth field-effect transistor; the gate control voltage is used to control the conduction of the ninth field-effect transistor. The enable module is specifically used to control the ninth field-effect transistor to be cut off when the negative voltage output circuit is in the working state, so as to prevent the control module from outputting control signals; and to control the ninth field-effect transistor to be turned on when the negative voltage output circuit is not in the working state, so as to enable the control module to output control signals.

[0010] In some possible implementations, the negative voltage output circuit includes a DC-to-DC circuit with negative voltage output.

[0011] In some possible implementations, the DC-to-DC circuit is any of the following: a charge pump circuit, a buck-boost chopper circuit.

[0012] Secondly, embodiments of this disclosure provide a negative voltage output circuit, which includes the adaptive discharge circuit of any of the embodiments of the first aspect described above.

[0013] Thirdly, embodiments of this disclosure provide a discharge method for an adaptive discharge circuit. The adaptive discharge circuit includes a discharge module, a control module, and an enable module. The control module is connected to both the discharge module and the enable module. The discharge module is connected to both a ground terminal and the negative voltage output terminal of a negative voltage output circuit. The method includes: When the negative voltage output circuit is in operation, the enable module disables the control module from outputting control signals; When the negative voltage output circuit is not in operation, the enable module enables the control module to output a control signal; The control signal is used to control the discharge module to discharge the output voltage of the negative voltage output terminal to the ground terminal.

[0014] The technical solutions provided by the embodiments of this disclosure may include the following beneficial effects: In this disclosure, the adaptive discharge circuit includes a discharge module, a control module, and an enable module. The control module is connected to both the discharge module and the enable module. The discharge module is connected to both the ground terminal and the negative voltage output terminal of the negative voltage output circuit. Specifically: the discharge module discharges the output voltage of the negative voltage output terminal to the ground terminal; the control module outputs a control signal for the discharge module, controlling its operation; and the enable module disables the control module from outputting the control signal when the negative voltage output circuit is in operation, and enables the control module to output the control signal when the negative voltage output circuit is not in operation. Therefore, when both the supply voltage to the negative voltage output circuit and the enable control signal are simultaneously removed, the output voltage of the negative voltage output terminal can be discharged to the ground terminal, thus preventing damage to related components. Attached Figure Description

[0015] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of the disclosure and to make other features, objects, and advantages of the disclosure more apparent. The illustrative embodiments of the disclosure, along with their descriptions, are used to explain the disclosure and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of an adaptive discharge circuit provided in an embodiment of the present disclosure; Figure 2This is a schematic diagram of the structure of a control module in an adaptive discharge circuit provided in an embodiment of the present disclosure; Figure 3 This is a schematic diagram of the structure of an enable module in an adaptive discharge circuit provided in an embodiment of the present disclosure; Figure 4 This is a schematic diagram of the structure of a discharge module in an adaptive discharge circuit provided in an embodiment of the present disclosure; Figure 5 This is a schematic diagram of another adaptive discharge circuit provided in an embodiment of the present disclosure; Figure 6 This is a schematic diagram of a negative voltage output circuit provided in an embodiment of the present disclosure; Figure 7 A flowchart of a discharge method for an adaptive discharge circuit provided in an embodiment of this disclosure. Detailed Implementation

[0016] To enable those skilled in the art to better understand the present disclosure, the technical solutions of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present disclosure, and not all embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present disclosure.

[0017] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this disclosure described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0018] In this disclosure, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this disclosure and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0019] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain circumstances to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this disclosure according to the specific circumstances.

[0020] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linked," and "socketing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0021] Figure 1 This is a schematic diagram of an adaptive discharge circuit provided in an embodiment of the present disclosure.

[0022] like Figure 1 As shown, the adaptive discharge circuit can be divided into three modules according to its function: a discharge module 10, a control module 20, and an enable module 30. The control module 20 is connected to both the discharge module 10 and the enable module 30. The discharge module 10 is connected to both the ground terminal GND and the negative voltage output terminal OUT of the negative voltage output circuit. Wherein: The discharge module 10 is used to discharge the output voltage of the negative voltage output terminal OUT to the ground terminal GND.

[0023] The control module 20 is used to output control signals to the discharge module 10, and to control the operation of the discharge module 10 through the control signals.

[0024] In some alternative implementations, the aforementioned control signal may be, for example, a voltage control signal or a current control signal.

[0025] The enable module 30 is used to disable the control module 20 from outputting control signals when the negative pressure output circuit is in operation, and to enable the control module 20 to output control signals when the negative pressure output circuit is not in operation.

[0026] In some alternative implementations, when the negative voltage output circuit is in operation, the discharge function of the adaptive discharge circuit can be turned off, and the discharge module 10 will not work; when the negative voltage output circuit is not in operation, the discharge function of the adaptive discharge circuit can be turned on, and the discharge module 10 will work.

[0027] In some alternative implementations, the negative voltage output circuit includes a DC-DC converter with negative voltage output.

[0028] In some application scenarios of the above-mentioned optional implementation methods, the DC-to-DC circuit is any one of the following: charge pump circuit, buck-boost chopper circuit.

[0029] In some alternative implementations, the functions of the discharge module 10, control module 20, and enable module 30 can be implemented by discrete devices or by chips with corresponding functions.

[0030] In this disclosure, the adaptive discharge circuit includes a discharge module, a control module, and an enable module. The control module is connected to both the discharge module and the enable module. The discharge module is connected to both the ground terminal and the negative voltage output terminal of the negative voltage output circuit. Specifically: the discharge module discharges the output voltage of the negative voltage output terminal to the ground terminal; the control module outputs a control signal for the discharge module, controlling its operation; and the enable module disables the control module from outputting the control signal when the negative voltage output circuit is in operation, and enables the control module to output the control signal when the negative voltage output circuit is not in operation. Therefore, when both the supply voltage to the negative voltage output circuit and the enable control signal are simultaneously removed, the output voltage of the negative voltage output terminal can be discharged to the ground terminal, thus preventing damage to related components.

[0031] Figure 2 This is a schematic diagram of the structure of a control module in an adaptive discharge circuit provided in an embodiment of this disclosure.

[0032] like Figure 2 As shown, the control module 20 includes a first resistor R1, a second resistor R2, a third resistor R3, a first field-effect transistor P1, a second field-effect transistor N4, a current mirror structure, a capacitor C1, and a diode D1. The current mirror structure includes a third field-effect transistor N1 and a fourth field-effect transistor N2.

[0033] The first terminal (e.g., gate) of the first field-effect transistor P1 is connected to the enable module 30, the second terminal (e.g., source) is connected to the power supply terminal VIN of the negative voltage output circuit through the second resistor R2, and the third terminal (e.g., drain) is connected to the third terminal (e.g., drain) of the fourth field-effect transistor N2.

[0034] The first terminal (e.g., gate) of the second field-effect transistor N4 is connected to the second terminal (e.g., source) of the third field-effect transistor N1, the second terminal (e.g., source) is connected to the discharge module 10, and the third terminal (e.g., drain) is connected to the second terminal (e.g., source) of the fourth field-effect transistor N2.

[0035] The first terminal (e.g., gate) of the third field-effect transistor N1 is connected to the first terminal (e.g., gate) of the fourth field-effect transistor N2, the second terminal (e.g., source) is connected to the discharge module 10 through the third resistor R3, and the third terminal (e.g., drain) is connected to the ground terminal GND through the first resistor R1.

[0036] The first terminal (e.g., gate) and the third terminal (e.g., drain) of the fourth field-effect transistor N2 are shorted; The first end of capacitor C1 is connected to the third end (e.g., the drain) of the first field-effect transistor P1, and the second end is connected to the discharge module 10.

[0037] The first end of diode D1 is connected to the third end (e.g., the drain) of the first field-effect transistor P1, and the second end is connected to the discharge module 10.

[0038] In some alternative implementations, the control module 20 may consist only of a first resistor R1, a second resistor R2, a third resistor R3, a first field-effect transistor P1, a second field-effect transistor N4, a capacitor C1, a diode D1, a third field-effect transistor N1, and a fourth field-effect transistor N2, without any other components. This simplifies the design of the control module and reduces circuit complexity.

[0039] In some alternative implementations, the control module 20 may include other components in addition to the first resistor R1, the second resistor R2, the third resistor R3, the first field-effect transistor P1, the second field-effect transistor N4, the capacitor C1, the diode D1, the third field-effect transistor N1, and the fourth field-effect transistor N2.

[0040] As can be understood, in this embodiment, when the negative voltage output circuit is turned off, current is generated in the path containing the second resistor R2. The current mirror structure mirrors this current to the branch of the third field-effect transistor N1 through the third field-effect transistor N1 and the fourth field-effect transistor N2, so that a stable voltage difference is generated across the third resistor R3, providing the gate control voltage for the second field-effect transistor N4. This, in turn, controls the module to output a stable control signal, and the discharge module 10 operates, discharging the output voltage of the negative voltage output terminal OUT to the ground terminal GND. Even if the power supply voltage of the negative voltage output circuit starts to drop, the current mirror structure can still maintain the voltage across the third resistor R3, ensuring that the discharge logic remains effective after the power supply voltage is removed.

[0041] Figure 3 This is a schematic diagram of the structure of an enable module in an adaptive discharge circuit provided in an embodiment of this disclosure.

[0042] like Figure 3 As shown, the enable module 30 includes a current source, a fifth resistor R5, a fifth field-effect transistor P3, a sixth field-effect transistor P4, a seventh field-effect transistor P2, and an eighth field-effect transistor N3.

[0043] The first terminal (e.g., gate) and the third terminal (e.g., drain) of the fifth field-effect transistor P3 are shorted. The first terminal (e.g., gate) of the fifth field-effect transistor P3 is connected to the first terminal (e.g., gate) of the sixth field-effect transistor P4. The second terminal (e.g., source) is connected to the power supply terminal VIN of the negative voltage output circuit. The third terminal (e.g., drain) is connected to the ground terminal GND through a current source.

[0044] The second terminal (e.g., the source) of the sixth field-effect transistor P4 is connected to the power supply terminal VIN of the negative voltage output circuit, and the third terminal (e.g., the drain) is connected to the second terminal (e.g., the source) of the seventh field-effect transistor P2.

[0045] The first terminal (e.g., the gate) of the seventh field-effect transistor P2 is connected to the enable signal terminal, and the third terminal (e.g., the drain) is connected to the control module 20 through the fifth resistor R5.

[0046] The first terminal (e.g., gate) of the eighth field-effect transistor N3 is connected to the third terminal (e.g., drain) of the seventh field-effect transistor P2, the second terminal (e.g., source) is connected to the negative voltage output terminal OUT, and the third terminal (e.g., drain) is connected to the control module 20.

[0047] It is understood that in the above embodiments, when the negative voltage output circuit is in normal working condition, the enable module 30 shuts off the output of the control module 20 through an enable signal (such as the first enable signal En_dis=0) to ensure that the discharge module 10 is closed, avoid affecting the normal output voltage, and prohibit discharge; when the negative voltage output circuit stops working (shutdown), the enable module 30 switches the enable signal (such as the first enable signal En_dis=1) to allow the control module 20 to output a control signal to discharge the residual voltage at the negative voltage output terminal to ground, prevent device damage, and enable discharge.

[0048] In some alternative implementations, the enable module 30 may also include a first inverter and a second inverter.

[0049] The first terminal (e.g., the gate) of the seventh field-effect transistor P2 is connected to the enable signal terminal through the first inverter and the second inverter.

[0050] It is understood that, in the above optional implementation methods, the enable module 30 can ensure the stability of the control signal through the first inverter and the second inverter.

[0051] Figure 4 This is a schematic diagram of the structure of a discharge module in an adaptive discharge circuit provided in an embodiment of this disclosure, as shown below. Figure 4 As shown, the discharge module 10 includes a ninth field-effect transistor, the Discharge MOS.

[0052] The first terminal (e.g., gate) of the ninth field-effect transistor Discharge MOS is connected to the control module 20, the second terminal (e.g., source) is connected to the negative voltage output terminal OUT, and the third terminal (e.g., drain) is connected to the ground terminal GND.

[0053] In some optional implementations of this embodiment, the control module 20 is specifically used to output the gate control voltage of the ninth field-effect transistor Discharge MOS; and to control the ninth field-effect transistor Discharge MOS to be turned on by the gate control voltage.

[0054] The enable module 30 is specifically used to control the ninth field-effect transistor Discharge MOS to be turned off when the negative voltage output circuit is in the working state, so as to prevent the control module 20 from outputting control signals; and to control the ninth field-effect transistor Discharge MOS to be turned on when the negative voltage output circuit is not in the working state, so as to enable the control module 20 to output control signals.

[0055] It is understood that in this embodiment, the operating state of the ninth field-effect transistor Discharge MOS is jointly determined by the logic signals of the control module 20 and the enable module 30. When the negative voltage output circuit shuts down, the ninth field-effect transistor Discharge MOS is turned on under the drive of the control module 20, discharging the residual voltage at the negative voltage output terminal to the ground terminal GND, thus preventing voltage residue from damaging related devices. When the circuit is working normally, the ninth field-effect transistor Discharge MOS is in the off state (VGS=0) under the control of the enable module 30, ensuring that the normal voltage at the negative voltage output terminal is not affected.

[0056] It should be noted that the technical features described in different embodiments can be combined with each other, and those skilled in the art can also make adjustments based on the technical inspiration of the described content to achieve the described functions, which will not be elaborated here.

[0057] The following describes the embodiments of this disclosure by way of example. However, it should be noted that the following content is only used to understand the technical solutions of the embodiments of this disclosure and does not constitute a limitation on the protection scope of the embodiments of this disclosure.

[0058] Figure 5 This is a schematic diagram of another adaptive discharge circuit provided in an embodiment of the present disclosure.

[0059] like Figure 5As shown, the adaptive discharge circuit can be divided into three modules according to its function. The discharge module 10 is composed of the ninth field-effect transistor Discharge MOS, which is responsible for discharging the output voltage to ground. The control module 20 is responsible for generating the gate control voltage (i.e., control signal) of the ninth field-effect transistor Diacharge MOS to ensure that the ninth field-effect transistor Diacharge MOS can be switched on and off. The enable module 30 is responsible for shutting down the ninth field-effect transistor Diacharge MOS to ensure that no leakage occurs when the discharge function is off, and for not affecting the generation of the gate voltage when the discharge function needs to be turned on.

[0060] When the negative voltage output circuit is working normally, the discharge function is turned off, and the control module 20 and the discharge module 10 are in the off state. The first enable signal En_dis output by the enable signal terminal of the enable module 30 is 0. The second enable signal enb output by the first enable signal terminal through the first inverter is 1. The third enable signal en output by the second enable signal enb through the second inverter is 0. At this time, the seventh field-effect transistor P2 is turned on, the gate voltage V1 of the eighth field-effect transistor is pulled high, the eighth field-effect transistor N3 is turned on, and the gate control voltage VGATE of the ninth field-effect transistor Diacharge MOS is equal to the output voltage (i.e., the output negative voltage) VOUT of the negative voltage output terminal. The gate control voltage of the ninth field-effect transistor Diacharge MOS is 0, and no output voltage is discharged.

[0061] When the negative voltage output circuit is off, En_dis=1, en=1, the first enable signal output from the enable signal terminal is converted to the second enable signal enb=0 after passing through the first inverter, V1 is pulled low, the control module 20 starts working, the first field-effect transistor P1 is turned on, and the seventh field-effect transistor P2 is turned off. Because there is a voltage difference across the second resistor R2, current is generated in the path of the second resistor R2. The third field-effect transistor N1 and the fourth field-effect transistor N2 form a current mirror structure, and current is also generated in the path of the third field-effect transistor N1. This generates the gate control voltage VGS4 of the second field-effect transistor N4 across the third resistor R3. At this time, VGATE=VGS4+VGS1+VOUT. Wherein, VGS1 represents the gate-source voltage of the third field-effect transistor N1, and VGS4 represents the gate-source voltage of the second field-effect transistor N4. The ninth field-effect transistor Discharge MOS is turned on, and the output negative voltage VOUT is discharged to ground. Capacitor C1 regulates the voltage of VGATE, and clamping diode D1 is used to protect the VGS voltage of the ninth field-effect transistor Discharge MOS from exceeding the withstand voltage value, which would damage the MOS transistor.

[0062] Because the VGATE voltage is always equal to the output negative voltage VOUT before the first MOSFET P1 is turned on, even when the power supply terminal VIN has started to lose power, the potential difference across the second resistor R2 remains high, ensuring current generation. Therefore, even if the power supply terminal VIN has been removed, this structure can still operate adaptively, ensuring that the output negative voltage VOUT can continue to be discharged to ground.

[0063] It should be noted that, in addition to the contents described above, this embodiment may also include the technical features described in the above embodiments, thereby achieving the technical effects of the above embodiments. Please refer to the above description for details. For the sake of brevity, it will not be elaborated here.

[0064] Based on the embodiments of this disclosure, when the power supply voltage and the enable signal at the enable signal terminal are simultaneously removed, the discharge circuit connected to the output terminal can still have logic, thereby ensuring that it continues to have the function of discharging.

[0065] Figure 6 This is a schematic diagram of a negative voltage output circuit provided in an embodiment of the present disclosure.

[0066] like Figure 6 As shown, the negative voltage output circuit includes the adaptive discharge circuit described in any of the above embodiments.

[0067] As an example, the adaptive discharge circuit includes a discharge module 10, a control module 20, and an enable module 30. The control module 20 is connected to both the discharge module 10 and the enable module 30. The discharge module 10 is connected to both the ground terminal GND and the negative voltage output terminal OUT of the negative voltage output circuit. The discharge module 10 is used to discharge the output voltage of the negative voltage output terminal OUT to the ground terminal GND; Control module 20 is used to output control signals to discharge module 10; and controls the operation of discharge module 10 through control signals. The enable module 30 is used to disable the control module 20 from outputting control signals when the negative pressure output circuit is in operation, and to enable the control module 20 to output control signals when the negative pressure output circuit is not in operation.

[0068] It should be noted that, in addition to the contents described above, this embodiment may also include the corresponding technical features described in the above embodiments, thereby achieving the corresponding technical effects. Please refer to the above description for details. For the sake of brevity, it will not be elaborated here.

[0069] It is understood that, in the embodiments of this disclosure, when the power supply voltage and the enable control signal of the negative voltage output circuit are simultaneously removed, the output voltage of the negative voltage output terminal can be discharged to the ground terminal, thereby avoiding damage to related components.

[0070] Figure 7 This is a flowchart of a discharge method for an adaptive discharge circuit provided in an embodiment of the present disclosure. The adaptive discharge circuit includes a discharge module 10, a control module 20, and an enable module 30. The control module 20 is connected to both the discharge module 10 and the enable module 30. The discharge module 10 is connected to both the ground terminal GND and the negative voltage output terminal OUT of the negative voltage output circuit.

[0071] like Figure 7 As shown, the method specifically includes: Step 101: When the negative pressure output circuit is in operation, enable module 30 disables control module 20 from outputting control signals.

[0072] Step 102: When the negative pressure output circuit is not in operation, enable module 30 enables control module 20 to output control signal.

[0073] The control signal is used to control the discharge module 10 to discharge the output voltage of the negative voltage output terminal OUT to the ground terminal GND.

[0074] It should be noted that, in addition to the contents described above, this embodiment may also include the corresponding technical features described in the above embodiments, thereby achieving the corresponding technical effects. Please refer to the above description for details. For the sake of brevity, it will not be elaborated here.

[0075] Based on the embodiments of this disclosure, when the power supply voltage and the enable control signal of the negative voltage output circuit are simultaneously removed, the output voltage of the negative voltage output terminal can be discharged to the ground terminal, thereby avoiding damage to related components.

[0076] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this disclosure.

[0077] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0078] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0079] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An adaptive discharge circuit, characterized in that, The adaptive discharge circuit includes a discharge module, a control module, and an enable module. The control module is connected to both the discharge module and the enable module. The discharge module is connected to both the ground terminal and the negative voltage output terminal of the negative voltage output circuit. The discharge module is used to discharge the output voltage of the negative voltage output terminal to the ground terminal; The control module is used to output control signals to the discharge module; and to control the operation of the discharge module through the control signals. The enabling module is used to disable the control module from outputting the control signal when the negative pressure output circuit is in the working state, and to enable the control module to output the control signal when the negative pressure output circuit is not in the working state.

2. The adaptive discharge circuit according to claim 1, characterized in that, The control module includes a first resistor, a second resistor, a third resistor, a first field-effect transistor, a second field-effect transistor, a current mirror structure, a capacitor, and a diode. The current mirror structure includes a third field-effect transistor and a fourth field-effect transistor. The first terminal of the first field-effect transistor is connected to the enable module, the second terminal is connected to the power supply terminal of the negative voltage output circuit through the second resistor, and the third terminal is connected to the third terminal of the fourth field-effect transistor. The first end of the second field-effect transistor is connected to the second end of the third field-effect transistor, the second end is connected to the discharge module, and the third end is connected to the second end of the fourth field-effect transistor. The first end of the third field-effect transistor is connected to the first end of the fourth field-effect transistor, the second end is connected to the discharge module through the third resistor, and the third end is connected to the ground terminal through the first resistor. The first and third terminals of the fourth field-effect transistor are shorted. The first end of the capacitor is connected to the third end of the first field-effect transistor, and the second end is connected to the discharge module. The first end of the diode is connected to the third end of the first field-effect transistor, and the second end is connected to the discharge module.

3. The adaptive discharge circuit according to claim 1, characterized in that, The enabling module includes a current source, a fifth resistor, a fifth field-effect transistor, a sixth field-effect transistor, a seventh field-effect transistor, and an eighth field-effect transistor; The first and third terminals of the fifth field-effect transistor are shorted together. The first terminal of the fifth field-effect transistor is connected to the first terminal of the sixth field-effect transistor. The second terminal is connected to the power supply terminal of the negative voltage output circuit. The third terminal is connected to the ground terminal through the current source. The second terminal of the sixth field-effect transistor is connected to the power supply terminal of the negative voltage output circuit, and the third terminal is connected to the second terminal of the seventh field-effect transistor. The first terminal of the seventh field-effect transistor is connected to the enable signal terminal, and the third terminal is connected to the control module through the fifth resistor. The first end of the eighth field-effect transistor is connected to the third end of the seventh field-effect transistor, the second end is connected to the negative voltage output terminal, and the third end is connected to the control module.

4. The adaptive discharge circuit according to claim 3, characterized in that, The enabling module further includes a first inverter and a second inverter; The first terminal of the seventh field-effect transistor is connected to the enable signal terminal through the first inverter and the second inverter.

5. The adaptive discharge circuit according to claim 1, characterized in that, The discharge module includes a ninth field-effect transistor; The first end of the ninth field-effect transistor is connected to the control module, the second end is connected to the negative voltage output terminal, and the third end is connected to the ground terminal.

6. The adaptive discharge circuit according to claim 5, characterized in that, The control module is specifically used to output the gate control voltage of the ninth field-effect transistor; and to control the ninth field-effect transistor to turn on through the gate control voltage; The enabling module is specifically used to control the ninth field-effect transistor to be cut off when the negative voltage output circuit is in the working state, so as to prevent the control module from outputting the control signal; and to control the ninth field-effect transistor to be turned on when the negative voltage output circuit is not in the working state, so as to enable the control module to output the control signal.

7. The adaptive discharge circuit according to any one of claims 1-6, characterized in that, The negative voltage output circuit includes a DC-to-DC circuit for negative voltage output.

8. The adaptive discharge circuit according to claim 7, characterized in that, The DC-to-DC circuit is any one of the following: a charge pump circuit or a step-up / step-down chopper circuit.

9. A negative voltage output circuit, characterized in that, The negative voltage output circuit includes the adaptive discharge circuit described in any one of claims 1-8.

10. A discharge method for an adaptive discharge circuit, characterized in that, The adaptive discharge circuit includes a discharge module, a control module, and an enable module. The control module is connected to both the discharge module and the enable module. The discharge module is connected to both a ground terminal and the negative voltage output terminal of the negative voltage output circuit. The method includes: When the negative pressure output circuit is in operation, the enable module disables the control module from outputting control signals; When the negative pressure output circuit is not in operation, the enabling module enables the control module to output the control signal; The control signal is used to control the discharge module to discharge the output voltage of the negative voltage output terminal to the ground terminal.

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