A starting circuit, starting device and chip

Abstract

The application belongs to the technical field of circuit design, and provides a starting circuit, a starting device and a chip. The starting circuit comprises a driving transistor, a direct current conversion module, a charge pump, a linear voltage stabilizing module and a feedback module. The direct current conversion module is used for voltage conversion processing of direct current output by the driving transistor. The charge pump boosts an input voltage signal provided by a power input end and provides a gate control signal for a gate of the driving transistor to control the driving transistor to be turned on. The linear voltage stabilizing module generates a power supply signal according to the input voltage signal provided by the power input end to supply power to the direct current conversion module. The feedback module compares the power supply signal with a preset threshold voltage, and when the voltage of the power supply signal is less than the preset threshold voltage, the charge pump charges an output end of the linear voltage stabilizing module to make the voltage of the output end of the linear voltage stabilizing module reach a preset voltage value, thereby ensuring that the circuit is normally started.

Description

Technical Field

[0001] This application belongs to the field of circuit design technology, and in particular relates to a startup circuit, startup device and chip. Background Technology

[0002] Chips (such as power control chips) are the core components of integrated circuits, and their normal operation plays a crucial role in ensuring the overall performance of the circuit. With the widespread application of chips, people have increasingly higher requirements for chip startup, such as fast startup time, low power consumption, and low cost. More importantly, the startup process of chips is required to meet certain stability requirements to ensure normal startup and stable operation.

[0003] However, the minimum input voltage for a typical DC-DC converter to operate normally is 3.3V. When the input voltage is less than 3.3V, the DC-DC converter will not function properly. Generally, with an input voltage of 5V, the output voltage of a low-dropout regulator (LDO) is 3.3V. However, when the power supply input voltage is unstable, for example, when the power supply voltage is less than 5V, the operating voltage provided by the LDO to the DC-DC converter will be even lower. In this case, the DC-DC converter will not function properly, and the circuit will fail to start. Summary of the Invention

[0004] The purpose of this application is to provide a startup circuit, startup device, and chip, which aims to solve the problem that the circuit cannot start when the power input voltage is low.

[0005] A first aspect of this application provides a startup circuit, the startup circuit comprising:

[0006] The driving transistor connected to the power input terminal;

[0007] A DC-DC converter module connected to the driving transistor is used to perform voltage conversion processing on the DC power output by the driving transistor;

[0008] A charge pump connected to the power input terminal and the driving transistor is used to boost the input voltage signal provided by the power input terminal and provide a gate control signal to the gate of the driving transistor.

[0009] A linear voltage regulator module connected to the power input terminal is used to generate a power supply signal based on the input voltage signal provided by the power input terminal, so as to supply power to the DC-DC conversion module;

[0010] The feedback module connected to the linear regulator module and the charge pump is used to compare the power supply signal with a preset threshold voltage, and when the voltage of the power supply signal is less than the preset threshold voltage, control the charge pump to charge the output terminal of the linear regulator module.

[0011] In one embodiment, the feedback module includes:

[0012] The voltage divider unit, connected to the linear voltage regulator module, is used to receive the power supply signal and perform voltage divider processing on the power supply signal to generate a voltage divider signal.

[0013] A comparison unit, connected to the voltage divider unit, is used to compare the voltage divider signal with a preset threshold voltage and generate a comparison signal based on the comparison result;

[0014] A current mirror unit, connected to the comparison unit, the linear regulator module, and the charge pump, is used to turn on according to the comparison signal so that the charge pump charges the output terminal of the linear regulator module.

[0015] In one embodiment, the voltage divider unit includes a first resistor and a second resistor. The first end of the first resistor is connected to the output terminal of the linear regulator module, and the second end of the first resistor and the first end of the second resistor are both connected to the comparator unit. The second end of the second resistor is grounded.

[0016] In one embodiment, at least one of the first resistor and the second resistor is an adjustable resistor.

[0017] In one embodiment, the comparison unit is a comparator.

[0018] In one embodiment, the current mirror unit includes: a current source, a diode, a first transistor, a second transistor, and a third transistor;

[0019] The cathode of the diode is connected to the output terminal of the linear voltage regulator module, the anode of the diode is connected to the first terminal of the first transistor, the control terminal of the first transistor is connected to the control terminal of the second transistor, the first terminal of the second transistor is connected to the first terminal of the third transistor, the second terminal of the first transistor and the second terminal of the second transistor are both connected to the charge pump, the control terminal of the third transistor is connected to the comparator unit, and the second terminal of the third transistor is connected to the current source.

[0020] In one embodiment, the driving transistor is an NMOS transistor.

[0021] In one embodiment, the linear regulator module includes: an operational amplifier, a third resistor, and a fourth resistor;

[0022] The non-inverting input terminal of the operational amplifier is connected to the power input terminal. The inverting input terminal of the operational amplifier, the first terminal of the third resistor, and the first terminal of the fourth resistor are all connected together. The output terminal of the operational amplifier and the second terminal of the third resistor are all connected to the DC-DC converter module. The second terminal of the fourth resistor is grounded.

[0023] A second aspect of this application also provides a starting device, the starting device including a starting circuit as described in any of the preceding claims.

[0024] A third aspect of this application also provides a chip including a startup circuit as described in any of the preceding embodiments.

[0025] This application provides a startup circuit, startup device, and chip. The startup circuit includes a driving transistor, a DC-DC converter module, a charge pump, a linear regulator module, and a feedback module. The DC-DC converter module performs voltage conversion on the DC output of the driving transistor. The charge pump boosts the input voltage signal provided by the power input terminal and provides a gate control signal to the gate of the driving transistor to control the driving transistor to turn on. The linear regulator module generates a power supply signal based on the input voltage signal provided by the power input terminal to power the DC-DC converter module. The feedback module compares the power supply signal with a preset threshold voltage. When the voltage of the power supply signal is less than the preset threshold voltage, the feedback module controls the charge pump to charge the output terminal of the linear regulator module so that the voltage at the output terminal of the linear regulator module reaches the preset voltage value, thereby ensuring normal circuit startup. Attached Figure Description

[0026] Figure 1 A circuit diagram of a startup circuit provided in an embodiment of this application;

[0027] Figure 2 A circuit diagram of another startup circuit provided in an embodiment of this application;

[0028] Figure 3 A circuit diagram of a linear voltage regulator module provided in an embodiment of this application;

[0029] Figure 4 A circuit diagram of a charge pump provided in an embodiment of this application. Detailed Implementation

[0030] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0031] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0032] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0034] The startup circuit includes a DC-DC converter, a charge pump (CHRPUMP), and a low dropout regulator (LDO). Its input power supply is generally around 3V to 30V. The input voltage is driven by the CHRPUMP to enter the DC-DC converter, and the other end is input to the LDO for further regulation to make its output stable and controllable. The third end is input to the CHRPUMP for boosting (gate voltage bootstrapping). Because the normal turn-on of an NMOS requires its gate voltage (VGATE) to be about 5V higher than its input voltage (VIN), the output of the CHRPUMP is generally 5V higher than the power supply input to meet the needs of the normal circuit.

[0035] Since the minimum input voltage for a DC-DC converter to operate normally is 3.3V, it will not function properly if the input voltage is less than 3.3V. Typically, a low dropout regulator (LDO) outputs 3.3V when the input voltage is 5V. However, when the power supply input voltage is unstable, for example, when the power supply voltage is less than 5V, the operating voltage provided by the LDO to the DC-DC converter will be even lower. In this case, the DC-DC converter will not function properly, and the circuit will fail to start.

[0036] To address the aforementioned technical problems, this application provides a startup circuit, see [link to relevant documentation]. Figure 1 As shown, the startup circuit includes: a driving transistor 20, a DC-DC converter module 30, a charge pump 40, a linear voltage regulator module 50, and a feedback module 60.

[0037] Specifically, the driving transistor 20 is connected to the power input terminal 10, and the DC-DC converter module 30 is connected to the driving transistor 20. The DC-DC converter module 30 is used to perform voltage conversion processing on the DC power output by the driving transistor 20. The charge pump 40 is connected to the power input terminal 10 and the driving transistor 20. The charge pump 40 is used to boost the input voltage signal provided by the power input terminal 10 and provide a gate control signal to the gate of the driving transistor 20. The linear regulator module 50 is connected to the power input terminal 10. The linear regulator module 50 is used to generate a power supply signal based on the input voltage signal provided by the power input terminal 10 to power the DC-DC converter module 30. The feedback module 60 is connected to the linear regulator module 50 and the charge pump 40 respectively. The feedback module 60 is used to compare the power supply signal with a preset threshold voltage, and when the voltage of the power supply signal is less than the preset threshold voltage, it controls the charge pump 40 to charge the output terminal of the linear regulator module 50.

[0038] In this embodiment, the feedback module 60 feeds back any insufficient power supply signal output from the linear regulator module 50 to the charge pump 40. The charge pump 40 then charges the output of the linear regulator module 50, thereby increasing the voltage at its output through the charging circuit. This ensures that the output power supply signal can power the DC-DC converter module 30. For example, the feedback module 60 compares the power supply signal with a preset threshold voltage. When the power supply signal voltage is less than the preset threshold voltage, the feedback module 60 connects the charging circuit between the charge pump 40 and the linear regulator module 50. This controls the charge pump 40 to charge the output of the linear regulator module 50, ensuring that the output voltage reaches the preset voltage value. This provides normal power to the DC-DC converter module 30 and guarantees normal circuit startup.

[0039] In one embodiment, see Figure 2 As shown, the feedback module 60 includes a voltage divider unit 61, a comparison unit 62, and a current mirror unit 63.

[0040] Specifically, voltage divider unit 61 is connected to linear regulator module 50 to receive power supply signal and perform voltage divider processing on the power supply signal to generate a voltage divider signal; comparison unit 62 is connected to voltage divider unit 61 to compare the voltage divider signal with a preset threshold voltage (Vref1) and generate a comparison signal based on the comparison result; current mirror unit 63 is connected to comparison unit 62, linear regulator module 50 and charge pump 40 respectively, and is used to turn on according to the comparison signal so that charge pump 40 charges the output terminal of linear regulator module 50. For example, if the voltage divider signal is less than the preset threshold voltage, the current mirror unit 63 charges the output terminal of linear regulator module 50.

[0041] In this embodiment, the power supply signal output from the output terminal of the linear regulator module 50 is used to power the DC-DC converter module 30. After being divided by the voltage divider unit 61, the power supply signal is output to the comparison unit 62. The comparison unit 62 compares the signal with a preset threshold voltage and generates a comparison signal based on the comparison result. The current mirror unit 63 controls the switching based on the level of the comparison signal. At this time, the current mirror unit 63 acts as a feedback charging circuit, which is turned on when the power supply signal output from the output terminal of the linear regulator module 50 is lower than the operating voltage of the DC-DC converter module 30, so that the charge pump 40 charges the linear regulator module 50 so that the power supply signal reaches the operating voltage of the DC-DC converter module 30.

[0042] For example, if the power supply signal output from the linear regulator module 50 meets the requirements and can supply power to the DC-DC converter module 30, the feedback charging circuit (i.e., the current mirror unit 63) will not be triggered. This feedback charging circuit is used to charge the output of the linear regulator module 50. When the power supply signal output from the linear regulator module 50 is lower than a certain threshold, the comparison signal output from the comparison unit 62 is reversed, and the feedback charging circuit is turned on. Since the voltage of the charge pump 40 is relatively high, the relatively high-voltage charge pump 40 charges the linear regulator module 50 through the feedback charging circuit. When the LDO output voltage meets the requirements after charging to a certain value, the comparison signal output from the comparison unit 62 is reversed again, and the charging feedback circuit is turned off.

[0043] In one embodiment, see Figure 2 As shown, the voltage divider unit 61 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is connected to the output terminal of the linear voltage regulator module 50. The second end of the first resistor R1 and the first end of the second resistor R2 are connected to the comparator unit 62. The second end of the second resistor R2 is grounded.

[0044] In this embodiment, the first resistor R1 and the second resistor R2 form a voltage divider circuit to divide the power supply signal output by the linear regulator module 50, so as to adjust the voltage of the power supply signal to the voltage matched by the comparator unit 62.

[0045] In one embodiment, at least one of the first resistor R1 and the second resistor R2 is an adjustable resistor.

[0046] In this embodiment, the voltage division ratio can be adjusted by adjusting the resistance value of the first resistor R1 or the second resistor R2, so that the startup circuit can adapt to different application scenarios.

[0047] In one embodiment, the comparison unit 62 is a comparator.

[0048] In one embodiment, see Figure 2 As shown, the current mirror unit 63 includes: a current source 631, a diode D1, a first transistor Q1, a second transistor Q2, and a third transistor Q3.

[0049] The cathode of diode D1 is connected to the output terminal of linear voltage regulator module 50, the anode of diode D1 is connected to the first terminal of first transistor Q1, the control terminal of first transistor Q1, the control terminal of second transistor Q2, and the first terminal of second transistor Q2 are all connected to the first terminal of third transistor Q3, the second terminal of first transistor Q1 and the second terminal of second transistor Q2 are all connected to charge pump 40, the control terminal of third transistor Q3 is connected to comparator unit 62, and the second terminal of third transistor Q3 is connected to current source 631.

[0050] In this embodiment, the current mirror unit 63 serves as a feedback charging circuit. It provides a reference current signal through a stable current source 631 and raises the voltage at the output terminal of the linear voltage regulator module 50 by connecting a stable current to a load resistor, so that its normal output value can reach the normal operating voltage of the DC-DC converter module 30. When the DC-DC converter module 30 can work normally, the output of the comparison unit 62 reverses, and the feedback charging circuit stops working, thereby controlling the voltage boost level at the output terminal of the linear voltage regulator module 50.

[0051] Specifically, the first transistor Q1 and the second transistor Q2 form a common source and common gate structure. If the voltage divider signal is less than the preset threshold voltage, the comparator unit 62 outputs a low-level comparator signal, the third transistor Q3 is turned on, the bias voltage is provided by the current source 631, the first transistor Q1 is turned on, and the mirror current is output to the output terminal of the linear regulator module 50 to ensure that the power supply signal output by the output terminal of the linear regulator module 50 meets the requirements and can supply power to the DC-DC converter module 30.

[0052] In one embodiment, the first transistor Q1, the second transistor Q2, and the third transistor Q3 are all PMOS transistors.

[0053] In one embodiment, the driving transistor 20 is an NMOS transistor.

[0054] In one embodiment, see Figure 3 As shown, the linear regulator module 50 includes: an operational amplifier 51, a third resistor R3, and a fourth resistor R4.

[0055] The non-inverting input of operational amplifier 51 is connected to the power input 10. The inverting input of operational amplifier 51, the first end of the third resistor R3 and the first end of the fourth resistor R4 are connected together. The output of operational amplifier 51 and the second end of the third resistor R3 are connected together to the DC-DC converter module 30. The second end of the fourth resistor R4 is grounded.

[0056] In this embodiment, the linear regulator module 50 can be a low-dropout linear stabilizer that uses a transistor or field-effect transistor (FET) operating in its saturation region to subtract excess voltage from the applied input voltage to produce a regulated output voltage. For example, in this embodiment, it functions to step down the voltage to power the DC-DC converter module 30.

[0057] Figure 3 The circuit diagram of a linear voltage regulator module 50 provided in this application embodiment shows that the voltages across the operational amplifier 51 are equal, and a voltage divider is used to generate a specific voltage by adjusting the size of the resistors.

[0058] Figure 4 This is a circuit schematic diagram of a charge pump 40 provided in an embodiment of this application. The charge pump 40 includes a first comparator 41, a fifth resistor R5, a sixth resistor R6, an oscillator 42, a gate voltage bootstrap circuit 43, and a fourth switch Q4.

[0059] Specifically, the first input terminal (i.e., the inverting input terminal) of the first comparator 41 is connected to the reference voltage source Vref2. The second input terminal (i.e., the non-inverting input terminal) of the first comparator 41 and the first terminal of the fifth resistor R5 are connected to the first terminal of the fourth switch Q4. The second terminal of the fifth resistor R5 is grounded. The output terminal of the first comparator 41 is connected to the input terminal of the oscillator 42. The output terminal of the oscillator 42 is connected to the gate voltage bootstrap circuit 43. The input terminal VIN of the gate voltage bootstrap circuit 43 and the control terminal (gate) of the fourth switch Q4 are connected to the power input terminal 10 for receiving the input voltage signal. The output terminal VCPOUT of the gate voltage bootstrap circuit 43 is connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is connected to the second terminal of the fourth switch Q4.

[0060] In this embodiment, the charge pump 40 raises the voltage at its input terminal VIN, making the voltage at its output terminal VCPOUT higher than the voltage at its input terminal VIN, and the voltage difference between the two is greater than a preset voltage value (e.g., 5V). The first comparator 41 compares the two voltages at its input terminals. When the comparison signal output by the comparator is high, the oscillator 42 generates an oscillation signal to activate the gate voltage bootstrap circuit 43. When the voltage at the output terminal VCPOUT of the gate voltage bootstrap circuit 43 is greater than the voltage at its input terminal VIN by a preset voltage value (e.g., the preset voltage value can be 5V), the fourth switch Q4 is turned on. Feedback is sent to the second input terminal of the first comparator 41 through the fourth switch Q4. At this time, the comparison signal output by the first comparator 41 flips, the oscillator 42 stops working, and the gate voltage bootstrap circuit 43 stops working, thus ensuring that the voltage at the output terminal VCPOUT of the charge pump 40 is only greater than the voltage at its input terminal VIN by a preset voltage value.

[0061] In one embodiment, the fourth switch Q4 can be a PMOS transistor.

[0062] This application also provides a starting device, which includes a starting circuit as described in any of the above embodiments.

[0063] This application also provides a chip including a startup circuit as described in any of the preceding embodiments.

[0064] This application provides a startup circuit, startup device, and chip. The startup circuit includes a driving transistor, a DC-DC converter module, a charge pump, a linear regulator module, and a feedback module. The DC-DC converter module performs voltage conversion on the DC output of the driving transistor. The charge pump boosts the input voltage signal provided by the power input terminal and provides a gate control signal to the gate of the driving transistor to control the driving transistor to turn on. The linear regulator module generates a power supply signal based on the input voltage signal provided by the power input terminal to power the DC-DC converter module. The feedback module compares the power supply signal with a preset threshold voltage. When the voltage of the power supply signal is less than the preset threshold voltage, the feedback module controls the charge pump to charge the output terminal of the linear regulator module so that the voltage at the output terminal of the linear regulator module reaches the preset voltage value, thereby ensuring normal circuit startup.

[0065] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0066] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0067] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0068] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0069] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A startup circuit, characterized in that, The startup circuit includes: The driving transistor connected to the power input terminal; A DC-DC converter module connected to the driving transistor is used to perform voltage conversion processing on the DC power output by the driving transistor; A charge pump connected to the power input terminal and the driving transistor is used to boost the input voltage signal provided by the power input terminal and provide a gate control signal to the gate of the driving transistor. A linear voltage regulator module connected to the power input terminal is used to generate a power supply signal based on the input voltage signal provided by the power input terminal, so as to supply power to the DC-DC conversion module; A feedback module connected to the linear regulator module and the charge pump is used to compare the power supply signal with a preset threshold voltage, and when the voltage of the power supply signal is less than the preset threshold voltage, control the charge pump to charge the output terminal of the linear regulator module; The feedback module includes: The voltage divider unit, connected to the linear voltage regulator module, is used to receive the power supply signal and perform voltage divider processing on the power supply signal to generate a voltage divider signal. A comparison unit, connected to the voltage divider unit, is used to compare the voltage divider signal with the preset threshold voltage and generate a comparison signal based on the comparison result; A current mirror unit, connected to the comparison unit, the linear regulator module, and the charge pump, is used to turn on according to the comparison signal, so that the charge pump charges the output terminal of the linear regulator module, so that the voltage at the output terminal of the linear regulator module reaches the preset threshold voltage. If the power supply signal output from the output terminal of the linear regulator module reaches the preset threshold voltage, power is supplied to the DC-DC converter module without triggering the current mirror unit, which is used to charge the output terminal of the linear regulator module. When the power supply signal output from the output terminal of the linear regulator module is lower than the preset threshold voltage, the comparison signal output by the comparison unit is reversed, and the current mirror unit is turned on. At this time, the charge pump charges the linear regulator module through the current mirror unit. When the preset threshold voltage is reached, the comparison signal output by the comparison unit is reversed again, and the current mirror unit is turned off.

2. The startup circuit as described in claim 1, characterized in that, The voltage divider unit includes a first resistor and a second resistor. The first end of the first resistor is connected to the output terminal of the linear voltage regulator module. The second end of the first resistor and the first end of the second resistor are both connected to the comparator unit. The second end of the second resistor is grounded.

3. The startup circuit as described in claim 2, characterized in that, At least one of the first resistor and the second resistor is an adjustable resistor.

4. The startup circuit as described in claim 1, characterized in that, The comparison unit is a comparator.

5. The startup circuit as described in claim 1, characterized in that, The current mirror unit includes: a current source, a diode, a first transistor, a second transistor, and a third transistor; The cathode of the diode is connected to the output terminal of the linear voltage regulator module, the anode of the diode is connected to the first terminal of the first transistor, the control terminal of the first transistor is connected to the control terminal of the second transistor, the first terminal of the second transistor is connected to the first terminal of the third transistor, the second terminal of the first transistor and the second terminal of the second transistor are both connected to the charge pump, the control terminal of the third transistor is connected to the comparator unit, and the second terminal of the third transistor is connected to the current source.

6. The startup circuit as described in claim 1, characterized in that, The driving transistor is an NMOS transistor.

7. The startup circuit as described in claim 1, characterized in that, The linear voltage regulator module includes: an operational amplifier, a third resistor, and a fourth resistor; The non-inverting input terminal of the operational amplifier is connected to the power input terminal. The inverting input terminal of the operational amplifier, the first terminal of the third resistor, and the first terminal of the fourth resistor are all connected together. The output terminal of the operational amplifier and the second terminal of the third resistor are all connected to the DC-DC converter module. The second terminal of the fourth resistor is grounded.

8. A starting device, characterized in that, The starting device includes the starting circuit as described in any one of claims 1-7.

9. A chip, characterized in that, Includes the startup circuit as described in any one of claims 1-7.

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