Power output control circuit and circuit board

Abstract

The embodiment of the invention discloses a power output control circuit and a circuit board. Besides the main power supply voltage, delayed switching-on and quick switching-off of other power supply voltages taking the main power supply voltage as a reference are realized through conventional electronic devices, so that power-on and power-off sequential logic control of different power supply voltages is realized, the hardware cost for realizing the power-on and power-off sequential logic control is reduced, and the power-on and power-off sequential logic control efficiency is improved. And the sequential logic control of power-on and power-off realized by a conventional electronic device is high in reliability.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and more particularly to power output control circuits and circuit boards. Background Technology

[0002] In electronic devices, there may be multiple functional modules that work together to achieve the intended functions of the device. These multiple functional modules may require multiple power supplies, each providing a different voltage. There may be timing logic requirements between these different power supplies during the power-on and power-off processes of the electronic device.

[0003] The inventors' research on existing timing logic control for power-on and power-off processes revealed that electronic devices typically employ dedicated logic control chips to achieve this timing logic control, resulting in high hardware costs for implementing such control in electronic devices. Summary of the Invention

[0004] This invention provides a power output control circuit and circuit board to solve the technical problem of high hardware costs required for implementing power-on and power-off timing logic control in existing electronic devices.

[0005] In a first aspect, embodiments of this application provide a power output control circuit, which includes a bootstrap boost sub-circuit, a first switching sub-circuit, a second switching transistor, a second switching sub-circuit, a third switching transistor, a third switching sub-circuit, a fourth switching transistor, and a fourth switching sub-circuit. The bootstrap boost sub-circuit includes a first voltage input terminal, a second voltage input terminal, and an output terminal. The first voltage input terminal and the second voltage input terminal are respectively used to connect a first DC voltage and a first AC voltage. The output terminal of the bootstrap boost sub-circuit is used to output a first control voltage when the first AC voltage is in a first polarity.

[0006] The first switching sub-circuit includes a first control terminal, a first connection terminal, and a second connection terminal; the first connection terminal is connected to the output terminal of the bootstrap boost sub-circuit, the second connection terminal is connected to the fourth input terminal of the fourth switching sub-circuit, and the first control terminal is connected to the third connection terminal of the second switching transistor.

[0007] The second input terminal of the second switch sub-circuit is used to connect to the first DC voltage. The second output terminal of the second switch sub-circuit is connected to the control terminal of the second switch transistor. The fourth connection terminal of the second switch transistor is connected to the fifth connection terminal of the third switch transistor. After the first DC voltage is powered on for a preset time, the second switch sub-circuit sends a second control signal to the control terminal of the second switch transistor to turn on the third connection terminal and the fourth connection terminal.

[0008] The third input terminal of the third switch sub-circuit is used to connect the first AC voltage. The third output terminal of the third switch sub-circuit is connected to the control terminal of the third switch transistor. The sixth connection terminal of the third switch transistor is grounded. When the first AC voltage is powered on, the third switch sub-circuit sends a third control signal to the control terminal of the third switch transistor to turn on the fifth connection terminal and the sixth connection terminal.

[0009] The fourth output terminal of the fourth switch sub-circuit is connected to the control terminal of the fourth switch transistor. The seventh connection terminal of the fourth switch transistor is used to connect to the second DC voltage. The eighth connection terminal of the fourth switch transistor is used to connect to the power module. The first DC voltage is greater than the second DC voltage.

[0010] When the third and fourth connection terminals are connected, and the fifth and sixth connection terminals are connected, a first control signal is sent to the first control terminal to connect the first and second connection terminals; when the first and second connection terminals are connected, the first control voltage controls the control terminal of the fourth switch to connect the seventh and eighth connection terminals.

[0011] In addition to the main power supply voltage, conventional electronic devices are used to delay the turn-on and quickly disconnect other power supply voltages that are referenced to the main power supply voltage. This enables the timing logic control of power-on and power-off for different power supply voltages, reducing the hardware cost of implementing the timing logic control of power-on and power-off. Moreover, the timing logic control of power-on and power-off implemented by conventional electronic devices has high reliability.

[0012] The bootstrap sub-circuit includes a boost capacitor and a first charging sub-circuit.

[0013] The two input terminals of the first charging sub-circuit are used as the first voltage input terminal and the second voltage input terminal, respectively. The output terminal of the first charging sub-circuit is connected to the first terminal of the boost capacitor as the output terminal of the bootstrap boost sub-circuit, and the second terminal of the boost capacitor is grounded.

[0014] The first charging electronic circuit controls the charging and discharging process of the boost capacitor, and supplies power to other power supply voltages that meet the timing logic control duration, thus completing the timing logic control of the power supply voltage.

[0015] The first charging electronic circuit includes a fourth resistor, a third capacitor, a fourth capacitor, a second diode, and a fourth diode.

[0016] The first terminal of the third capacitor is used to connect to the first AC power. The second terminal of the third capacitor is connected to the positive terminal of the second diode and the negative terminal of the fourth diode. The positive terminal of the fourth diode is connected to the first terminal of the boost capacitor and the first terminal of the fourth resistor and is used to connect to the first DC voltage. The negative terminal of the second diode is connected to the second terminal of the boost capacitor, the second terminal of the fourth resistor and the first terminal of the fourth capacitor, and outputs the first control voltage when the first AC voltage is in the first polarity. The second terminal of the fourth capacitor is grounded.

[0017] The above describes how the timing logic control of the power supply voltage is achieved by using specific hardware circuits to conduct power to other power supply voltages that meet the timing logic control requirements.

[0018] Among them, the second switch sub-circuit includes a voltage drop control sub-circuit, a delay sub-circuit, and an electron discharge circuit;

[0019] The first terminal of the voltage drop control sub-circuit and the first terminal of the discharge circuit are both used to connect to the first DC voltage. The second terminal of the voltage drop control sub-circuit is connected to the first terminal of the delay sub-circuit. The middle terminal of the delay sub-circuit is connected to the second terminal of the discharge circuit and the control terminal of the second switching transistor. The second terminal of the delay sub-circuit is connected to the fourth connection terminal of the second switching transistor.

[0020] As described above, when the first DC voltage is powered on, the voltage at the second output terminal is controlled to gradually increase by controlling the input terminal of the voltage drop control sub-circuit, thereby controlling the power supply of the power supply voltage that is powered on later, and ensuring that different power supply voltages are powered on according to the corresponding timing logic control.

[0021] The voltage drop control sub-circuit includes multiple diodes connected in series in the same direction. The positive terminals of the series-connected diodes correspond to the first terminal of the voltage drop control sub-circuit, and the negative terminals of the series-connected diodes correspond to the second terminal of the voltage drop control sub-circuit.

[0022] As described above, the power supply voltage that is powered on later is controlled by the voltage drop of multiple diodes, ensuring that different power supply voltages are powered on according to their corresponding timing logic control.

[0023] The delay sub-circuit includes an eighth resistor and a seventh capacitor; the first end of the eighth resistor serves as the first end of the delay sub-circuit, the second end of the eighth resistor is connected to the first end of the seventh capacitor as the middle end of the delay sub-circuit, and the second end of the seventh capacitor serves as the second end of the delay sub-circuit.

[0024] As described above, through the eighth resistor and the seventh capacitor, the power can be discharged quickly when the power is off, so that the power supply voltage that needs to be turned off first stops supplying power.

[0025] The second switch sub-circuit also includes a ninth resistor, which is connected in parallel with the seventh capacitor.

[0026] As mentioned above, the ninth resistor, acting as a bleeder, further ensures the safe operation of the circuit.

[0027] The discharge circuit includes a fifth diode; the negative terminal of the fifth diode serves as the first terminal of the discharge circuit, and the positive terminal of the fifth diode serves as the second terminal of the discharge circuit.

[0028] As described above, the fifth diode can quickly discharge the capacitor in the delay sub-circuit, thereby achieving the function of quickly turning off the second switching transistor.

[0029] The third switching sub-circuit includes the second charging sub-circuit and the ninth capacitor;

[0030] The two input terminals of the second charging electronic circuit are respectively used as the third input terminal and ground. The output terminal of the second charging electronic circuit is connected to the first terminal of the ninth capacitor as the third output terminal. The second terminal of the ninth capacitor is grounded.

[0031] When the first AC voltage is de-energized, the third switch sub-circuit disconnects the power supply to the control terminal of the third switching transistor within a preset response time.

[0032] As described above, when the main power supply voltage is disconnected and powered off, the third switch sub-circuit quickly disconnects the power supply to the control terminal of the third switch tube within a preset response time, causing the output of other power supply voltages to immediately become zero. However, since the main power supply voltage usually has a large-capacity capacitor in the power supply circuit, it is turned off with a delayed time compared to other power supply voltages, thus realizing the timing logic control when powered off.

[0033] The second charging electronic circuit includes an eighth capacitor, a ninth diode, and a tenth diode;

[0034] The first terminal of the eighth capacitor is used as the third input terminal to connect to the first AC voltage. The second terminal of the eighth capacitor is connected to the positive terminal of the ninth diode and the negative terminal of the tenth diode. The negative terminal of the ninth diode serves as the output terminal of the second charging electronic circuit and is connected to the first terminal of the ninth capacitor and the control terminal of the third switching transistor. The positive terminal of the tenth diode is grounded.

[0035] As described above, through a specific hardware circuit, when the main power supply voltage is disconnected and powered off, the third switch sub-circuit immediately turns off, causing the output of other power supply voltages to immediately become zero. Since the main power supply voltage usually has a large-capacity capacitor in the power supply circuit, it turns off with a delay compared to other power supply voltages, thus realizing the timing logic control when power is off.

[0036] The fourth switch sub-circuit includes a voltage divider sub-circuit and a power-off control sub-circuit;

[0037] The input terminal of the voltage divider circuit is used to divide the first control voltage when the first control voltage is applied, so that the control terminal of the fourth switch can control the seventh and eighth connection terminals to be turned on.

[0038] The first terminal of the power-off control sub-circuit is connected to the control terminal of the fourth switch transistor, and the second terminal of the power-off control sub-circuit is grounded. When the first control voltage disappears, the control voltage of the control terminal of the fourth switch transistor is pulled to ground so that the control terminal of the fourth switch transistor controls the disconnection of the seventh and eighth connection terminals.

[0039] As described above, the first control voltage is supplied to the fourth switch transistor through the fourth switch sub-circuit for control. When the hardware control condition with the main power supply voltage as a reference is met, the first control voltage controls the power supply of the second DC voltage to be turned on, and the power is applied after the main power supply voltage. When the main power supply voltage is turned off, the hardware control condition with the main power supply voltage as a reference is not met, the first control voltage disappears quickly, and the power supply of the second DC voltage is turned off quickly accordingly. This is equivalent to the second DC voltage being turned off in advance before the main power supply voltage, which can be delayed in turning off, is completely turned off, thus realizing the timing logic control during power-off.

[0040] The voltage divider circuit includes a second resistor and a sixth resistor;

[0041] The first end of the second resistor is used to connect to the first control voltage. The second end of the second resistor is connected to the control terminal of the fourth switch and the first end of the sixth resistor. The second end of the sixth resistor is connected to the eighth connection terminal.

[0042] As described above, the first control voltage is divided by conventional second and sixth resistor components to turn on the fourth switch.

[0043] The power-off control sub-circuit includes a third diode and a thirteenth resistor;

[0044] The first terminal of the thirteenth resistor is connected to the negative terminal of the third diode, and the second terminal of the thirteenth resistor is grounded; the positive terminal of the third diode is connected to the control terminal of the fourth switch.

[0045] As described above, by using conventional third diode and thirteenth resistor components, the control voltage at the control terminal of the fourth switch is quickly pulled to ground, thereby achieving rapid turn-off of the fourth switch.

[0046] The fourth switch sub-circuit also includes a short-circuit control sub-circuit. The first terminal of the short-circuit control sub-circuit is used to connect to the first DC voltage, and the second terminal of the short-circuit control sub-circuit is connected to the seventh connection terminal.

[0047] As described above, the short-circuit control sub-circuit enables the simultaneous shutdown of all power supply branches when the first DC voltage output is short-circuited.

[0048] The short-circuit control sub-circuit includes a first diode, with the cathode of the first diode serving as the first terminal of the short-circuit control sub-circuit and the anode of the first diode serving as the second terminal of the short-circuit control sub-circuit.

[0049] The above describes how a conventional first diode component enables the simultaneous shutdown of all power supply branches when the first DC voltage output is short-circuited. The first switching sub-circuit includes a first transistor, a fifth resistor, and a seventh resistor.

[0050] The emitter of the first transistor is connected to the first terminal of the fifth resistor as the first connection terminal. The second terminal of the fifth resistor is connected to the first terminal of the seventh resistor and the base of the first transistor. The second terminal of the seventh resistor serves as the first control terminal. The collector of the first transistor serves as the second connection terminal.

[0051] As described above, by using transistors and resistors, precise and stable control of power supply voltages other than the main power supply voltage can be achieved at low cost.

[0052] Secondly, embodiments of this application provide a circuit board that includes the power output control circuit of any one of the first aspects.

[0053] The circuit board of this application embodiment has the same beneficial effects as the corresponding power output control circuit. Attached Figure Description

[0054] Figure 1 The circuit diagram of the power output control circuit provided in the embodiment of this application. Detailed Implementation

[0055] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and not for limiting the invention. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention and not the entire structure.

[0056] It should be noted that, due to space limitations, this application specification does not exhaustively list all possible implementation methods. Those skilled in the art should be able to conceive after reading this application specification that, as long as the technical features do not contradict each other, any combination of technical features can constitute an optional implementation method.

[0057] The embodiments of the present invention will be described in detail below.

[0058] Electronic devices typically contain different functional modules, such as modules for storage, data processing, audio acquisition, and sensing. These different modules may have corresponding power supply voltage requirements, and there are also power-on / off timing logic control requirements between these different power supply voltage requirements. For example, when powering on with two different power supply voltages, the higher voltage needs to be applied for a duration T1 before the lower voltage; when powering off, the higher voltage needs to be applied for a duration T2 after the lower voltage.

[0059] The inventors' research on existing timing logic control for power-on and power-off processes revealed that electronic devices typically employ dedicated logic control chips to achieve this timing logic control, resulting in high hardware costs for implementing such control in electronic devices.

[0060] To address the aforementioned technical problems, embodiments of this application propose a power output control circuit and circuit board. In addition to the main power supply voltage, conventional electronic devices are used to achieve delayed turn-on and rapid turn-off of other power supply voltages with the main power supply voltage as a reference. This enables timing logic control of power-on and power-off for different power supply voltages, reducing the hardware cost of implementing timing logic control for power-on and power-off. Moreover, the timing logic control for power-on and power-off implemented with conventional electronic devices has high reliability.

[0061] Please refer to Figure 1 This is a circuit diagram of the power output control circuit provided in this embodiment. The power output control circuit includes a bootstrap boost sub-circuit 11, a first switching sub-circuit 15, and a second switching transistor (…). Figure 1 The example shown is the second transistor QM2), the second switching sub-circuit 12, and the third switching transistor ( Figure 1 The example shown is the third MOSFET QM3), the third switch sub-circuit 13, and the fourth switch ( Figure 1The example circuit includes a first MOSFET (Q1) and a fourth switching sub-circuit 14 (excluding the first MOSFET Q1 within the corresponding dashed box). The bootstrap sub-circuit 11 includes a first voltage input terminal, a second voltage input terminal, and an output terminal. The first and second voltage input terminals are respectively used to connect to a first DC voltage and a first AC voltage. The output terminal of the bootstrap sub-circuit 11 is used to output a first control voltage when the first AC voltage is in a first polarity. The first switching sub-circuit 15 includes a first control terminal, a first connection terminal, and a second connection terminal. The first connection terminal is connected to the output terminal of the bootstrap sub-circuit 11, the second connection terminal is connected to the fourth input terminal of the fourth switching sub-circuit 14, and the first control terminal is connected to the third connection terminal of the second switching transistor. The second input terminal of the second switching sub-circuit 12 is used to connect to the first DC voltage. The second output terminal of the second switching sub-circuit 12 is connected to the control terminal of the second switching transistor, and the fourth connection terminal of the second switching transistor is connected to the fifth connection terminal of the third switching transistor. The second switching sub-circuit 12 is used to power on the first DC voltage to a preset value. After a period of time, a second control signal is sent to the control terminal of the second switch transistor to turn on the third and fourth connection terminals; the third input terminal of the third switch sub-circuit 13 is used to connect to the first AC voltage, the third output terminal of the third switch sub-circuit 13 is connected to the control terminal of the third switch transistor, the sixth connection terminal of the third switch transistor is grounded, and the third switch sub-circuit 13 is used to send a third control signal to the control terminal of the third switch transistor when the first AC voltage is powered on to turn on the fifth and sixth connection terminals; the fourth output terminal of the fourth switch sub-circuit 14 is connected to the control terminal of the fourth switch transistor, the seventh connection terminal of the fourth switch transistor is used to connect to the second DC voltage, and the eighth connection terminal of the fourth switch transistor is used to connect to the power module, the first DC voltage is greater than the second DC voltage; when the third and fourth connection terminals are turned on, and the fifth and sixth connection terminals are turned on, a first control signal is sent to the first control terminal to turn on the first and second connection terminals; when the first and second connection terminals are turned on, the first control voltage controls the control terminal of the fourth switch transistor to turn on the seventh and eighth connection terminals.

[0062] In electronic devices using the power output control circuit of the embodiments of this application, although there may be multiple power supply voltages, they can generally be divided into main power supply voltage and other power supply voltages. The main power supply voltage refers to the power supply voltage that powers on earliest and powers off latest during one working cycle of the electronic device from power-on to power-off. For example, the maximum DC voltage that ensures the overall power supply (i.e., the first DC voltage, for example...). Figure 1 The various 4.2V voltages shown), AC voltage input through a transformer, etc.; other supply voltages refer to supply voltages whose power-on time is later than that of the main supply voltage and whose power-off time is earlier than that of the main supply voltage. Other supply voltages are usually DC voltages and are smaller than the maximum DC voltage, defined as the second DC voltage (e.g., Figure 1(The voltage shown is 3.3V). During the entire power supply process of the electronic device, the main power supply voltage is the most stable. Based on this, this application embodiment designs multiple switching sub-circuits and switching transistors with the main power supply voltage as a reference. The power supply duration of the main power supply voltage triggers each switching sub-circuit to control the on / off state of the switching transistor, thereby controlling the power-on and power-off of other power supply voltages. This application embodiment also defines multiple connection terminals from the first connection terminal to the eighth connection terminal. These connection terminals are grouped in pairs, and each group of connection terminals corresponds to a switching transistor. They are controlled by a corresponding sub-circuit with switching control function. A group of connection terminals in the same switching transistor is turned on or off according to the driving state of the corresponding control terminal. A group of connection terminals can be understood as equivalent to the moving end and the stationary end of a mechanical switch. Under different control, the circuit state between the moving end and the stationary end (i.e., the two connection terminals in the same group) can be switched to the on or off state.

[0063] Regarding the power supply process of a single other power supply voltage, in order to ensure delayed power-on and earlier power-off compared to the main power supply voltage, a specific switch sub-circuit (i.e., the fourth switch sub-circuit 14) is designed to control the on / off state of the corresponding fourth switch transistor. To control the on / off state of the fourth switch transistor, a bootstrap sub-circuit 11 is specifically designed as a drive circuit to provide the conduction voltage to the fourth switch sub-circuit 14 corresponding to the fourth switch transistor. The bootstrap sub-circuit 11 and the fourth switch sub-circuit 14 are connected to a first switch sub-circuit 15. The conduction state of the switch transistor in the first switch sub-circuit 15 determines whether the bootstrap sub-circuit 11 provides the drive voltage to drive the fourth switch transistor to the fourth switch sub-circuit 14. The conduction timing of the switch transistor in the first switch sub-circuit 15 is determined by the on / off state of the second and third switch transistors. The on / off state of the second and third switch transistors is determined by the state of the electronic devices in the second switch sub-circuit 12 and the third switch sub-circuit 13 after the main power supply voltage is powered on and off, and the drive voltage provided in the corresponding state. Specifically, after the main power supply voltage is powered on, it affects the state of the electronic components in the second and third switch sub-circuits 12 and 13, ultimately causing the second and third switching transistors to turn on or off accordingly. Only when the second and third switching transistors are simultaneously on will the switching transistor in the first switch sub-circuit 15 be in the on state. The second switch sub-circuit 12 can precisely control the on-time of the second switching transistor, correspondingly controlling how long after the first DC voltage is powered on, the second DC voltage is powered on. The third switch sub-circuit 13 can quickly disconnect the third switching transistor after the first DC voltage is powered off, correspondingly controlling the second DC voltage to power off almost simultaneously with the first DC voltage. However, the first DC voltage will power off later than the second DC voltage due to the standard large-capacity capacitor. In other words, the first DC voltage powers off later than the second DC voltage. Combining the above sub-circuits and the combined control logic of the corresponding switching transistors, it can be seen that with only basic electronic components, the precise timing logic control of different power supply voltages can be achieved directly through hardware circuits.

[0064] Overall, in addition to the main power supply voltage, conventional electronic devices are used to achieve delayed switching on and rapid switching off of other power supply voltages referenced to the main power supply voltage. This enables the timing logic control of power-on and power-off for different power supply voltages, reducing the hardware cost of implementing the timing logic control of power-on and power-off. Moreover, the timing logic control of power-on and power-off implemented by conventional electronic devices has high reliability.

[0065] In one specific implementation, the bootstrap boost circuit 11 includes a boost capacitor and a first charging circuit 111. The two input terminals of the first charging circuit 111 serve as a first voltage input terminal and a second voltage input terminal, respectively, for connecting a first DC voltage and a first AC voltage. The output terminal of the first charging circuit 111 is connected to the first terminal of the boost capacitor as the output terminal of the bootstrap boost circuit, and the second terminal of the boost capacitor is grounded. The first charging circuit 111 controls the charging and discharging process of the boost capacitor and supplies power to other supply voltages that meet the timing logic control requirements, thus completing the timing logic control of the supply voltage.

[0066] Please refer to Figure 1 The bootstrap boost circuit 11 may include a fourth resistor R4, a third capacitor C3, a fourth capacitor C4, a boost capacitor C5, a second diode D2, and a fourth diode D4; wherein the first charging circuit 111 includes a fourth resistor R4, a third capacitor C3, a fourth capacitor C4, a second diode D2, and a fourth diode D4, and the bootstrap boost circuit 11 may also include a third resistor R3. The first terminal of the third resistor R3 is used to connect to a first AC voltage, the second terminal of the third resistor R3 is connected to the first terminal of the third capacitor C3, the second terminal of the third capacitor C3 is connected to the positive terminal of the second diode D2 and the negative terminal of the fourth diode D4; the positive terminal of the fourth diode D4 is connected to the first terminal of the boost capacitor C5 and the first terminal of the fourth resistor R4 and connected to a first DC voltage; the negative terminal of the second diode D2 is connected to the second terminal of the boost capacitor C5, the second terminal of the fourth resistor R4, and the first terminal of the fourth capacitor C4, and outputs a first control voltage when the first AC voltage is in the first polarity, and the second terminal of the fourth capacitor C4 is grounded. It should be understood that, given the high safety of the electronic components in the first charging electronic circuit 111 and the boost capacitor C5, the third resistor R3 may not be required, meaning that the first terminal of the third capacitor C3 can be directly connected to the first AC power supply.

[0067] exist Figure 1In the bootstrap sub-circuit 11 implemented in the power output control circuit shown, the first AC voltage is the secondary side of the 4.2V transformer, and the first DC voltage is also 4.2V. When the polarity of the 4.2V transformer winding is negative, the 4.2V main output charges the third capacitor C3 through the fourth diode D4. The third resistor R3 is a current-limiting resistor used to prevent excessive pulse current. At this time, the voltage polarity on the third capacitor C3 is negative on the left and positive on the right, and its amplitude is equal to the negative polarity voltage of the transformer. When the polarity of the 4.2V transformer winding is positive, the voltage of the transformer winding and the third capacitor C3 charges the boost capacitor C5 through the second diode D2. At this time, the voltage on the boost capacitor C5 is equal to the voltage of the third capacitor C3 plus the positive polarity voltage of the 4.2V transformer winding. Meanwhile, since the voltage of boost capacitor C5 is superimposed on the main output circuit of the first DC voltage of 4.2V, the voltage on the fourth capacitor C4 is equal to 4.2V + the voltage of the third capacitor C3 + the positive polarity voltage of the 4.2V transformer winding, approximately equal to 10V~15V. This voltage is sufficient to turn on the first switching sub-circuit 15. The specific hardware circuit then supplies power to other power supply voltages that meet the timing logic control duration, thus completing the timing logic control of the power supply voltage. Of course, in actual implementation, the bootstrap boost sub-circuit 11 can be fine-tuned so that when the polarity of the 4.2V transformer winding is negative, it outputs a voltage of 10V~15V. That is, the first polarity can be positive or negative, depending on the overall output requirements.

[0068] In another specific implementation, the second switching sub-circuit 12 includes a voltage drop control sub-circuit 121, a delay sub-circuit 122, and a discharge circuit. The first terminal of both the voltage drop control sub-circuit 121 and the first terminal of the discharge circuit are connected to a first DC voltage. The second terminal of the voltage drop control sub-circuit 121 is connected to the first terminal of the delay sub-circuit 122. The middle terminal of the delay sub-circuit 122 is connected to the second terminal of the discharge circuit and the control terminal of the second switching transistor. The second terminal of the delay sub-circuit 122 is connected to the fourth connection terminal of the second switching transistor. The delay sub-circuit 122 typically achieves delay control through multiple series-connected components. In this embodiment, the connection point between two adjacent components in the series-connected components is defined as the middle terminal.

[0069] When the first DC voltage is applied via the input terminal of the voltage drop control subcircuit 121, because there is a transistor voltage drop smaller than the first DC voltage, there is no drive signal for the second switching transistor before the transistor voltage drop is reached during the voltage rise from 0V to the first DC voltage. Only when the voltage rises to equal or exceed the transistor voltage drop will there be a drive signal for the second switching transistor. This drive signal keeps the third and fourth connection terminals on through the second control terminal, thereby controlling the power supply of the later-powered supply voltage and ensuring that different supply voltages are powered on according to their corresponding timing logic control. The second switching subcircuit 12 only defines one output terminal, the second output terminal. This definition is only used to distinguish the output terminal of the second switching subcircuit 12 from the output terminal of the bootstrap voltage boost subcircuit 11, and does not mean that the second switching subcircuit 12 necessarily has other output terminals. The definition of the third output terminal, fourth output terminal, etc. of other switching subcircuits is the same.

[0070] Please refer to Figure 1 The second switching sub-circuit 12 may include a fifth diode D5, a sixth diode D6, a seventh diode D7, an eighth diode D8, an eighth resistor R8, a ninth resistor R9, and a seventh capacitor C7; wherein the voltage drop control sub-circuit 121 includes a sixth diode D6, a seventh diode D7, and an eighth diode D8; the delay sub-circuit 122 includes an eighth resistor R8 and a seventh capacitor C7; the second switching sub-circuit 12 also includes a ninth resistor R9; the discharge circuit includes a fifth diode D5; and the second switching transistor is a second transistor QM2. The anode of the sixth diode D6 is connected to the cathode of the fifth diode D5 and used to apply the first DC voltage. The cathode of the sixth diode D6 is connected to the anode of the seventh diode D7. The cathode of the seventh diode D7 is connected to the anode of the eighth diode D8. The cathode of the eighth diode D8 is connected to the first terminal of the eighth resistor R8. The second terminal of the eighth diode D8 is connected to the anode of the fifth diode D5, the first terminal of the seventh capacitor C7, the first terminal of the ninth resistor R9, and the base of the second transistor QM2. The emitter of the second transistor QM2 serves as the fourth connection terminal and is connected to the second terminal of the seventh capacitor C7 and the second terminal of the ninth resistor R9. The collector of the second transistor QM2 serves as the third connection terminal.

[0071] In its implementation, the voltage drop control sub-circuit 121 may include multiple diodes connected in series in the same direction. The positive terminals of the series-connected diodes correspond to the first terminal of the voltage drop control sub-circuit, and the negative terminals of the series-connected diodes correspond to the second terminal of the voltage drop control sub-circuit. For diodes with polarity, being connected in series in the same direction can be considered as having polarity as a whole, and the polarity corresponds to the direction of any one of the diodes. In this embodiment, the end of the series-connected diodes corresponding to the positive terminal of a single diode is defined as the positive terminal, and the other end of the whole is defined as the negative terminal. Figure 1The example shown is an implementation with three diodes (i.e., the sixth diode D6, the seventh diode D7, and the eighth diode D8), but in practice, there can be two, four, or more diodes.

[0072] It should be understood that, in the embodiments of this application, the specific circuit implementations of the voltage drop control sub-circuit 121, the delay sub-circuit 122, and the discharge circuit are comprehensively described. Additionally, a ninth resistor R9 is provided. These specific circuit implementations can all be implemented independently and do not necessarily imply that they are identical to those of the voltage drop control sub-circuit 121, the delay sub-circuit 122, and the discharge circuit. Figure 1 The specific implementation methods of other sub-circuits presented are used in conjunction with each other. For example, the voltage drop control sub-circuit 121 can achieve the same voltage drop control effect using only a diode with suitable parameters. The implementation of other specific circuits in the following sections also presents similar methods.

[0073] exist Figure 1 In the second switching sub-circuit 12 implemented in the power output control circuit shown, the combined voltage drop of the sixth diode D6, the seventh diode D7, and the eighth diode D8 is approximately 3.3V. Therefore, during the process of the 4.2V voltage rising from 0V to 4.2V, the second transistor QM2 conducts when the voltage is greater than or equal to 3.3V. That is, the first DC voltage of 4.2V can be directly applied, while the second DC voltage of 3.3V needs to rise from 0V to 3.3V after the 4.2V voltage is applied to achieve the circuit conduction state for the second DC voltage of 3.3V. This ensures that the first DC voltage of 4.2V is output before the second DC voltage of 3.3V. The required delay time T1 can be achieved by changing the eighth resistor R8 and the seventh capacitor C7. The ninth resistor R9 is a bleeder resistor, and the fifth diode D5 mainly discharges the seventh capacitor C7 quickly, achieving the function of quickly turning off the second transistor QM2. By controlling the voltage drop across multiple diodes, the power supply voltage that is powered on later in the sequence is controlled, ensuring that different power supply voltages are powered on according to their corresponding timing logic control. During power failure, rapid discharge also stops the power supply voltage that needs to be powered off first. In the specific implementation, the sixth diode D6, the seventh diode D7, and the eighth diode D8 can be replaced entirely with a single Zener diode, which can also achieve the corresponding timing logic control.

[0074] In another specific implementation, the third switching sub-circuit includes a second charging sub-circuit 131 and a ninth capacitor C9. The two input terminals of the second charging sub-circuit 131 serve as the third input terminal and ground, respectively. The output terminal of the second charging sub-circuit 131 is connected to the first terminal of the ninth capacitor C9 as the third output terminal, and the second terminal of the ninth capacitor C9 is grounded. When the first AC voltage is de-energized, the third switching sub-circuit 131 disconnects the power supply to the control terminal of the third switching transistor within a preset response time. When the main power supply voltage is de-energized, the third switching sub-circuit quickly disconnects the power supply to the control terminal of the third switching transistor within a preset response time, causing the output of other power supply voltages to immediately become zero. Since the main power supply voltage typically has a large-capacity capacitor in its power supply circuit, it is de-energized with a delayed turn-off time compared to other power supply voltages, thus achieving sequential logic control during power-down.

[0075] Please refer to Figure 1 The third switching sub-circuit 13 may include a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, an eighth capacitor C8, a ninth capacitor C9, a ninth diode D9, and a tenth diode D10; the second charging sub-circuit may include an eighth capacitor C8, a ninth diode D9, and a tenth diode D10, and may also include a tenth resistor R10, an eleventh resistor R11, and a twelfth resistor R12, and the third switching transistor is a third MOSFET QM3. The first terminal of the tenth resistor R10 is used to connect to the first AC voltage. The second terminal of the tenth resistor R10 is connected to the first terminal of the eighth capacitor C8. The second terminal of the eighth capacitor C8 is connected to the anode of the ninth diode D9 and the cathode of the tenth diode D10. The cathode of the ninth diode D9 is connected to the first terminal of the ninth capacitor C9 and the first terminal of the eleventh resistor R11. The second terminal of the eleventh resistor R11 is connected to the gate of the third MOSFET QM3. The source of the third MOSFET QM3 is grounded as the sixth connection terminal and is connected to the anode of the tenth diode D10, the second terminal of the ninth capacitor C9, and the second terminal of the twelfth resistor R12. The drain of the third MOSFET QM3 is the fifth connection terminal. The tenth resistor R10, eleventh resistor R11, and twelfth resistor R12 are used to achieve current limiting protection or voltage division circuit effects to improve the overall stability of the power output control circuit.

[0076] Because there is a large-capacity filter capacitor in the main output circuit corresponding to the first DC voltage of 4.2V, the 4.2V drops very slowly under extremely light load. The third switching sub-circuit 13 ensures that the branch corresponding to the second DC voltage of 3.3V can be turned off before the branch corresponding to 4.2V is turned off. The third switching sub-circuit 13 is also a bootstrap circuit in terms of circuit type. The difference between the third switching sub-circuit 13 and the bootstrap sub-circuit 11 is that the positive terminal of the tenth diode D10 is grounded and is no longer superimposed on 4.2V. Because the conduction control voltage of the third MOSFET QM3 comes from the 4.2V transformer winding, and the capacitance values ​​of the eighth capacitor C8 and the ninth capacitor C9 are very small, the response is rapid. When the 4.2V branch has no output, the third MOSFET QM3 immediately turns off, causing the switching transistor in the first switching sub-circuit 15 to turn off, which in turn causes the fourth switching sub-circuit 14 to turn off the fourth switching transistor. The output of the 3.3V branch immediately becomes zero, while the 4.2V main output circuit, due to the presence of a large-capacity capacitor, can turn off with a delay of T2 compared to the 3.3V branch. Through the specific hardware circuit, when the main power supply voltage is disconnected and powered down, the third switching sub-circuit 13 immediately turns off the third switching transistor (i.e., the third MOSFET QM3), causing the output of other power supply voltages to immediately become zero. The main power supply voltage, due to the presence of a large-capacity capacitor in the power supply circuit, can turn off with a delay compared to other power supply voltages, thus achieving timing logic control during power-down.

[0077] In another alternative implementation, please refer to Figure 1 The first switching sub-circuit 15 may include a first transistor QM1 (i.e., the switching transistor in the first switching sub-circuit 15), a fifth resistor R5, and a seventh resistor R7. The emitter of the first transistor QM1 is connected as the first connection terminal to the first terminal of the fifth resistor R5. The second terminal of the fifth resistor R5 is connected to the first terminal of the seventh resistor R7 and the base of the first transistor QM1. The second terminal of the seventh resistor R7 serves as the first control terminal. The collector of the first transistor QM1 serves as the second connection terminal. The first transistor QM1 conducts when both the second switching transistor (i.e., the second transistor QM2) and the third switching transistor (i.e., the third MOSFET QM3) are turned on, thereby completing the bootstrap boost sub-circuit 11 to provide the fourth switching sub-circuit 14 with the conduction drive for controlling the switching of the fourth switching transistor. Through transistors and resistors, precise and stable control of other supply voltages besides the main supply voltage can be achieved at low cost.

[0078] In one optional implementation, the fourth switching sub-circuit 14 includes a voltage divider sub-circuit 141 and a power-off control sub-circuit 142. The input terminal of the voltage divider sub-circuit 141 is used to divide the first control voltage when the first control voltage is applied, so that the control terminal of the fourth switching transistor controls the seventh connection terminal and the eighth connection terminal to be turned on. The first terminal of the power-off control sub-circuit 142 is connected to the control terminal of the fourth switching transistor, and the second terminal of the power-off control sub-circuit 142 is grounded. It is used to pull the control voltage of the control terminal of the fourth switching transistor to ground when the first control voltage disappears, so that the control terminal of the fourth switching transistor controls the seventh connection terminal and the eighth connection terminal to be turned off. The first control voltage is supplied to the fourth switch transistor through the fourth switch sub-circuit 14 for control. When the hardware control condition with reference to the main power supply voltage is met, the first control voltage controls the power supply of the second DC voltage to be turned on, and it is powered on after the main power supply voltage. When the main power supply voltage is turned off, the hardware control condition with reference to the main power supply voltage is not met, the first control voltage disappears quickly, and the power supply of the second DC voltage is turned off quickly because the control voltage on which its power supply circuit relies to maintain conduction disappears quickly. This is equivalent to the second DC voltage being turned off in advance before the main power supply voltage, which itself can delay the turn-off, is completely turned off, thus realizing the timing logic control when the power is turned off.

[0079] In addition, the third switching sub-circuit 14 may also include a short-circuit control sub-circuit. The first terminal of the short-circuit control sub-circuit is used to connect to the first DC voltage, and the second terminal of the short-circuit control sub-circuit is connected to the seventh connection terminal. Through the short-circuit control sub-circuit, all power supply branches are simultaneously turned off when the first DC voltage output is short-circuited.

[0080] Please refer to Figure 1The fourth switching sub-circuit 14 includes a first resistor R1, a second resistor R2, a sixth resistor R6, a thirteenth resistor R13, a first capacitor C1, a second capacitor C2, a first diode D1, a third diode D3, and a first MOSFET Q1; the voltage divider sub-circuit 141 includes a second resistor R2 and a sixth resistor R6; the power-off control sub-circuit 142 includes a third diode D3 and a thirteenth resistor R13; the short-circuit control sub-circuit includes a first diode D1; the fourth switching transistor is the first MOSFET Q1; the first capacitor C1, the second capacitor C2, and the first resistor R1, etc., can be used to achieve filtering, noise reduction, and other circuit effects to improve the working stability of the entire power output control circuit. The first terminal of the thirteenth resistor R13, the first terminal of the second resistor R2, and the cathode of the third diode D3 are connected and connected to the first control voltage. The second terminal of the thirteenth resistor R13, the first terminal of the first resistor R1, and the first terminal of the second capacitor C2 are grounded. The second terminal of the second resistor R2 is connected to the anode of the third diode D3, the gate of the first MOSFET Q1, the first terminal of the first capacitor C1, and the first terminal of the sixth resistor R6. The source of the first MOSFET Q1 serves as the eighth connection terminal and is connected to the second terminal of the first capacitor C1, the second terminal of the sixth resistor R6, the second terminal of the first resistor R1, and the second terminal of the second capacitor C2. The drain of the first MOSFET Q1 serves as the seventh connection terminal and is connected to the anode of the first diode D1. The cathode of the first diode D1 is used to connect to the first DC voltage.

[0081] When the first transistor QM1 is turned on, the voltage across the fourth capacitor C4 is divided by the second resistor R2 and the sixth resistor R6, causing the first MOSFET Q1 to turn on. When the first transistor QM1 is turned off, the gate voltage of the first MOSFET Q1 is quickly pulled to ground through the third diode D3 and the thirteenth resistor R13, achieving rapid turn-off of the first MOSFET Q1. The function of the first diode D1 is to quickly pull down the 3.3V branch when the 4.2V output is short-circuited, thereby achieving simultaneous turn-off of the 3.3V branch and the 4.2V branch. Through the specific hardware circuit, when the hardware control conditions with reference to the main supply voltage are met, the second DC voltage is turned on, powering on after the main supply voltage; when the main supply voltage is turned off, the hardware control conditions with reference to the main supply voltage are not met, and the second DC voltage is quickly turned off. This is equivalent to the second DC voltage being turned off before the main supply voltage, which itself can delay turn-off, is fully turned off, realizing the timing logic control during power-off.

[0082] It should be understood that, in practical implementation, MOSFETs and transistors are the most common electronic devices for implementing on / off control. MOSFETs and transistors can be used interchangeably, meaning that various switching transistors can be flexibly selected from various electronic devices that can implement on / off control.

[0083] This application provides a circuit board that includes the power supply circuit described in any of the preceding embodiments. This circuit board may be, for example, the motherboard of a personal computer or an interactive flat panel.

[0084] The circuit board provided in this embodiment has the same beneficial effects as the power output control circuit mentioned above. It can significantly reduce the hardware cost of implementing the timing logic control for power-on and power-off. Moreover, the timing logic control for power-on and power-off implemented by conventional electronic devices has high reliability, thereby improving the market competitiveness of products at each stage.

[0085] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0086] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A power output control circuit, characterized in that, It includes a bootstrap boost circuit, a first switching circuit, a second switching transistor, a second switching circuit, a third switching transistor, a third switching circuit, a fourth switching transistor, and a fourth switching circuit. The bootstrap boost circuit includes a first voltage input terminal, a second voltage input terminal, and an output terminal; the first voltage input terminal and the second voltage input terminal are respectively used to connect a first DC voltage and a first AC voltage, and the output terminal of the bootstrap boost circuit is used to output a first control voltage when the first AC voltage is in a first polarity; The first switching sub-circuit includes a first control terminal, a first connection terminal, and a second connection terminal; the first connection terminal is connected to the output terminal of the bootstrap boost sub-circuit, the second connection terminal is connected to the fourth input terminal of the fourth switching sub-circuit, and the first control terminal is connected to the third connection terminal of the second switching transistor. The second input terminal of the second switch sub-circuit is used to connect to the first DC voltage. The second output terminal of the second switch sub-circuit is connected to the control terminal of the second switch transistor. The fourth connection terminal of the second switch transistor is connected to the fifth connection terminal of the third switch transistor. After the first DC voltage is powered on for a preset time, the second switch sub-circuit sends a second control signal to the control terminal of the second switch transistor to turn on the third connection terminal and the fourth connection terminal. The third input terminal of the third switch sub-circuit is used to connect to the first AC voltage. The third output terminal of the third switch sub-circuit is connected to the control terminal of the third switch transistor. The sixth connection terminal of the third switch transistor is grounded. When the first AC voltage is powered on, the third switch sub-circuit sends a third control signal to the control terminal of the third switch transistor to turn on the fifth connection terminal and the sixth connection terminal. The fourth output terminal of the fourth switch sub-circuit is connected to the control terminal of the fourth switch transistor. The seventh connection terminal of the fourth switch transistor is used to connect to the second DC voltage. The eighth connection terminal of the fourth switch transistor is used to connect to the power module. The first DC voltage is greater than the second DC voltage. When the third and fourth connection terminals are connected, and the fifth and sixth connection terminals are connected, a first control signal is sent to the first control terminal to connect the first and second connection terminals; when the first and second connection terminals are connected, the first control voltage controls the control terminal of the fourth switch to connect the seventh and eighth connection terminals.

2. The power output control circuit according to claim 1, characterized in that, The bootstrap boost sub-circuit includes a boost capacitor and a first charging sub-circuit. The two input terminals of the first charging sub-circuit are respectively used as the first voltage input terminal and the second voltage input terminal. The output terminal of the first charging sub-circuit is connected to the first terminal of the boost capacitor as the output terminal of the bootstrap boost sub-circuit, and the second terminal of the boost capacitor is grounded.

3. The power output control circuit according to claim 2, characterized in that, The first charging electronic circuit includes a fourth resistor, a third capacitor, a fourth capacitor, a second diode, and a fourth diode; The first terminal of the third capacitor is used to connect to the first AC voltage, and the second terminal of the third capacitor is connected to the positive terminal of the second diode and the negative terminal of the fourth diode. The positive terminal of the fourth diode is connected to the first terminal of the boost capacitor and the first terminal of the fourth resistor and is used to connect to the first DC voltage. The negative terminal of the second diode is connected to the second terminal of the boost capacitor, the second terminal of the fourth resistor and the first terminal of the fourth capacitor, and outputs a first control voltage when the first AC voltage is in the first polarity. The second terminal of the fourth capacitor is grounded.

4. The power output control circuit according to any one of claims 1-3, characterized in that, The second switching sub-circuit includes a voltage drop control sub-circuit, a delay sub-circuit, and an electron discharge circuit; The first terminal of the voltage drop control sub-circuit and the first terminal of the discharge circuit are both used to connect to the first DC voltage. The second terminal of the voltage drop control sub-circuit is connected to the first terminal of the delay sub-circuit. The middle terminal of the delay sub-circuit is connected to the second terminal of the discharge circuit and the control terminal of the second switching transistor. The second terminal of the delay sub-circuit is connected to the fourth connection terminal of the second switching transistor.

5. The power output control circuit according to claim 4, characterized in that, The voltage drop control subcircuit includes multiple diodes connected in series in the same direction. The positive terminals of the multiple diodes connected in series serve as the first terminal of the voltage drop control subcircuit, and the negative terminals of the multiple diodes connected in series serve as the second terminal of the voltage drop control subcircuit.

6. The power output control circuit according to claim 4, characterized in that, The delay sub-circuit includes an eighth resistor and a seventh capacitor; the first end of the eighth resistor serves as the first end of the delay sub-circuit, the second end of the eighth resistor is connected to the first end of the seventh capacitor as the middle end of the delay sub-circuit, and the second end of the seventh capacitor serves as the second end of the delay sub-circuit.

7. The power output control circuit according to claim 6, characterized in that, The second switch sub-circuit also includes a ninth resistor, which is connected in parallel with the seventh capacitor.

8. The power output control circuit according to claim 4, characterized in that, The electron discharge circuit includes a fifth diode; the negative terminal of the fifth diode serves as the first terminal of the electron discharge circuit, and the positive terminal of the fifth diode serves as the second terminal of the electron discharge circuit.

9. The power output control circuit according to any one of claims 1-3, characterized in that, The third switching sub-circuit includes a second charging sub-circuit and a ninth capacitor; The two input terminals of the second charging sub-circuit are respectively used as the third input terminal and ground. The output terminal of the second charging sub-circuit is connected to the first terminal of the ninth capacitor as the third output terminal. The second terminal of the ninth capacitor is grounded. When the first AC voltage is de-energized, the third switch sub-circuit disconnects the power supply to the control terminal of the third switch tube within a preset response time.

10. The power output control circuit according to claim 9, characterized in that, The second charging electronic circuit includes an eighth capacitor, a ninth diode, and a tenth diode; The first terminal of the eighth capacitor is used as the third input terminal to connect to the first AC voltage. The second terminal of the eighth capacitor is connected to the positive terminal of the ninth diode and the negative terminal of the tenth diode. The negative terminal of the ninth diode is connected as the output terminal of the second charging electronic circuit to the first terminal of the ninth capacitor and the control terminal of the third switching transistor. The positive terminal of the tenth diode is grounded.

11. The power output control circuit according to any one of claims 1-3, characterized in that, The fourth switch sub-circuit includes a voltage divider sub-circuit and a power-off control sub-circuit; The input terminal of the voltage divider circuit is used to divide the first control voltage when the first control voltage is connected, so that the control terminal of the fourth switch can control the conduction of the seventh connection terminal and the eighth connection terminal. The first terminal of the power-off control sub-circuit is connected to the control terminal of the fourth switch transistor, and the second terminal of the power-off control sub-circuit is grounded. When the first control voltage disappears, the control voltage of the control terminal of the fourth switch transistor is pulled to ground, so that the control terminal of the fourth switch transistor controls the disconnection of the seventh connection terminal and the eighth connection terminal.

12. The power output control circuit according to claim 11, characterized in that, The voltage divider circuit includes a second resistor and a sixth resistor; The first end of the second resistor is used to connect to the first control voltage, the second end of the second resistor is connected to the control terminal of the fourth switch and the first end of the sixth resistor, and the second end of the sixth resistor is connected to the eighth connection terminal.

13. The power output control circuit according to claim 11, characterized in that, The power-off control sub-circuit includes a third diode and a thirteenth resistor; The first terminal of the thirteenth resistor is connected to the negative terminal of the third diode, and the second terminal of the thirteenth resistor is grounded; the positive terminal of the third diode is connected to the control terminal of the fourth switch.

14. The power output control circuit according to claim 11, characterized in that, The fourth switch sub-circuit also includes a short-circuit control sub-circuit, the first terminal of which is used to connect to the first DC voltage, and the second terminal of which is connected to the seventh connection terminal.

15. The power output control circuit according to claim 14, characterized in that, The short-circuit control sub-circuit includes a first diode, the negative terminal of which serves as the first terminal of the short-circuit control sub-circuit, and the positive terminal of which serves as the second terminal of the short-circuit control sub-circuit.

16. The power output control circuit according to any one of claims 1-3, characterized in that, The first switching sub-circuit includes a first transistor, a fifth resistor, and a seventh resistor; The emitter of the first transistor is connected to the first terminal of the fifth resistor as the first connection terminal. The second terminal of the fifth resistor is connected to the first terminal of the seventh resistor and the base of the first transistor. The second terminal of the seventh resistor serves as the first control terminal. The collector of the first transistor serves as the second connection terminal.

17. A circuit board, characterized in that, Includes the power output control circuit as described in any one of claims 1-16.

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