CN205453657U - Startup/shutdown circuit - Google Patents

Abstract

The utility model relates to a switching machine circuit, which solves the deficiencies in the prior art. The technical proposal is: the output end of the LDO power supply circuit is electrically connected with the input end of the switch control circuit, and the first output end of the switch control circuit is connected with the logical OR operation The first input end of the circuit is connected, the first output end of the switch control circuit is also electrically connected with the reset port of the switch machine control chip through the reset circuit, and the second output end of the switch control circuit is electrically connected with an input and output port of the switch machine control chip Connection, the second input terminal of the logic or operation circuit is connected with an input and output port of the switch machine control chip, the output of the logic or operation circuit is connected with the enabling terminal of the DC-DC power supply circuit, and the output terminal of the DC-DC power supply circuit They are respectively connected to the power supply end of the reset circuit and the power supply port of the switch control chip, and the input terminal of the indicator light circuit and the control terminal of the buzzer circuit are both electrically connected to an input and output port of the switch control chip.

Description

switch circuit

technical field

The utility model relates to a medical instrument, in particular to a switch circuit.

Background technique

In many electronic products, a commonly used switch mode is realized in this way. The switch control chip is always in the working state, continuously monitoring the action of the switch button, and when the switch button is triggered, the start or shutdown command is executed. This commonly used switch mode, for some portable battery-powered devices, when the device is in the off state, because the switch control chip is still working, it will inevitably consume a part of the battery capacity. This part of capacity may seem insignificant, but in practical applications, it is one of the important factors affecting battery life. At the same time, when most similar devices adopt this power-on/off method, the energy consumed by power-on detection cannot be ignored. Today, when energy conservation and environmental protection are advocated, designing a better switching method can not only avoid this unnecessary waste of resources, but also is very necessary for batteries.

Utility model content

The purpose of the utility model is to solve the problem in the prior art that a part of the battery capacity is inevitably consumed because the switch control chip is still working, and to provide a switch circuit that can avoid this unnecessary waste of resources.

The technical solution adopted by the utility model to solve the technical problem is: a switch machine circuit, powered by the battery of the equipment, including LDO power supply circuit, logic or operation circuit, switch control circuit, reset circuit, switch machine control chip, DC-DC Power supply circuit, indicator light circuit and buzzer circuit, the input end of the DC-DC power supply circuit is connected to the device battery, the input end of the LDO power supply circuit is connected to the device battery, the output end of the LDO power supply circuit is connected to the input end of the switch control circuit connection, the first output end of the switch control circuit is connected with the first input end of the logic or operation circuit, the first output end of the switch control circuit is also electrically connected with the reset port of the switch machine control chip through the reset circuit, and the first output end of the switch control circuit is electrically connected with the reset port of the switch machine control chip. The two output terminals are electrically connected to an input and output port of the switch machine control chip, the second input terminal of the logic or operation circuit is connected to an input and output port of the switch machine control chip, and the output of the logic or operation circuit is connected to the DC-DC power supply circuit The enabling terminal of the DC-DC power supply circuit is connected to the power supply terminal of the reset circuit and the power supply port of the switch machine control chip respectively, and the input terminal of the indicator light circuit and the control terminal of the buzzer circuit are connected to the control terminal of the buzzer circuit. An input and output port of the switch machine control chip is electrically connected. In the utility model, STM32F103C8T6 or other control chips can be used as the switch control chip, the LDO power supply circuit can use XC6202P332PR chip or similar LDO power supply chip, and the DC-DC power supply circuit can use MP1584DC-DC power supply chip or similar DC-DC power supply chip , when the utility model is used, as long as one of the switch control circuit or the switch control chip outputs a control signal, the DC-DC power supply chip can start to supply power. Completely cut off the power, and the utility model is provided with a reset circuit, the switch machine control chip can be forced to reset through the reset circuit, the use method is almost the same as the existing switch circuit, but the switch machine control chip can be completely powered off, thereby saving electric energy.

Preferably, the input end of the indicator light circuit is also connected to the first input end of the logic or operation circuit.

As preferably, the power supply end of the buzzer circuit is connected with the output end of the DC-DC power supply circuit,

Preferably, the logical OR operation circuit is an OR gate, the first input end of the OR gate is electrically connected to an input and output port of the switch machine control chip, and the second input end of the OR gate is electrically connected to the first output end of the switch control circuit, The output terminal of the OR gate is connected with the enabling terminal of the DC-DC power supply circuit.

Preferably, the logic or operation circuit includes a first diode for realizing the OR gate function and a second diode for realizing the OR gate function, and the anode of the first diode for realizing the OR gate function is electrically connected to an input and output port of the switch machine control chip. The anode of the second diode is connected to the first output terminal of the switch control circuit to realize the OR gate function, and the cathode of the first diode to realize the OR gate function and the second diode to realize the OR gate function are both connected to the DC -Enable terminal connection of the DC power supply circuit.

Preferably, the enabling end of the DC-DC power supply circuit is also grounded through a resistor R4. When shutting down, because the resistor R4 is pulled down to the ground, the DC-DC power supply circuit shuts down and has no output, until the enable terminal of the DC-DC power supply circuit is at a high level, the DC-DC power supply circuit outputs current to supply power to the switch machine control chip .

Preferably, the switch control circuit includes a transistor U4, a resistor R10, a button K1, a resistor R9, a capacitor C9, a resistor R11, a resistor R12, and a capacitor C10, and the first end of the button K1 is connected to the collector of the transistor U4 , the second end of the button K1 is connected to the base of the transistor U4 through a resistor R10, the second end of the button K1 is also grounded through a resistor R9, and the collector of the transistor U4 is connected to the output end of the LDO power supply circuit, The base of the triode U4 is grounded through the capacitor C9, the emitter of the triode U4 is grounded through the resistor R11, the emitters of the triode U4 are respectively connected to the first input terminal of the logic or operation circuit, and the emitter of the triode U4 is controlled by the reset circuit and the switch The reset port of the chip is electrically connected, the emitter of the transistor U4 is also connected to the first end of the resistor R12, the second end of the resistor R12 is grounded through the capacitor C10, and the second end of the resistor R12 is also connected to an input and output port of the switch control chip electrical connection. Take the STM32F103C8T6 switch control chip as an example. When the button K1 is not pressed, the transistor U4 is not turned on, and the output is at a continuous low level; when the button K1 is pressed, the transistor U4 is turned on, and the output is continuous. high level. When the triode U4 emits a very high level, the enabling terminal of the DC-DC power supply circuit is also high, and the DC-DC power supply circuit starts to work, and the output current supplies power to the reset circuit and the switch control chip. The power-on reset of the switch machine control chip outputs a high-level signal to the first input terminal of the logic or operation circuit to ensure that the enable terminal of the DC-DC power supply circuit is continuously high, so that the DC-DC power supply circuit is always in the working state. At this time Release the button K1 to complete the boot process. After starting up, when the button K1 is pressed again, the switch machine control chip will detect that the emitter of the transistor U4 changes from low level to high level, and at this time the switch machine control chip is powered on and resets to output a low level signal to the logic or The first input terminal of the operation circuit can be turned off. The function of capacitor C9 in the switch control circuit is to debounce the button. The function of resistor R12 and capacitor C10 is to ensure that the signal passing through resistor R12 will have a certain delay, and the signal will be slower than the signal directly collected from the emitter of triode U4, ensuring There is no signal at the VDDA terminal of the switch machine control chip before power-on.

Preferably, the reset circuit includes a resistor R14, a resistor R13, a capacitor C11, a capacitor C12 and a field effect transistor U6, the drain of the field effect transistor U6 is connected to the output terminal of the DC-DC power supply circuit through the resistor R14, and the field effect transistor U6 The grid of the transistor U6 is connected to the emitter of the transistor U4 through the resistor R13, the gate of the MOSFET U6 is grounded through the capacitor C11, the source of the MOSFET U6 is grounded, the drain of the MOSFET U6 is grounded through the capacitor C12, and the MOSFET The drain of U6 is electrically connected to an input and output port of the switch machine control chip. Take the STM32F103C8T6 switch control chip as an example, in which the resistor R14 and capacitor C12 complete the reset action of the switch control chip at the moment of power-on. After starting up, the button K1 is released, the gate of the field effect transistor U6 is at low level, the field effect transistor U6 is turned off, and the RESET terminal of the switch control chip is continuously at high level. When there is a problem with the device program and the shutdown program cannot be executed, press the button K1 often, the gate of the field effect transistor U6 will change from low level to high level, and the capacitor C11 will be charged through the resistor R13. When the charging voltage reaches the open level of the field effect transistor U6 , the field effect transistor U6 is turned on, and the switch control chip changes from high level to low level, which can forcibly reset the switch control chip.

The substantive effect of the utility model is: after the utility model is shut down, there is no output after the DC-DC power supply circuit is shut off, and the switch machine control chip is completely powered off, that is, the switch machine control chip does not consume battery capacity after the shutdown, and at the same time , This solution realizes single-button power-on, power-off and reset operations, and has sound and indicator light prompt functions, which can prevent equipment users from misoperation.

Description of drawings

Fig. 1 is a kind of circuit schematic diagram of switching machine control chip in the utility model;

Fig. 2 is a kind of circuit diagram of LDO power supply circuit in the utility model;

Fig. 3 is a kind of circuit diagram of DC-DC power supply circuit in the utility model;

Fig. 4 is a kind of circuit diagram of switch control circuit in the utility model;

Fig. 5 is a kind of circuit diagram of reset circuit in the utility model;

FIG. 6 is a schematic circuit diagram of a logic or operation circuit in the present invention.

detailed description

The technical solutions of the present utility model will be further specifically described below through specific embodiments in conjunction with the accompanying drawings.

Example 1:

A switch machine circuit, powered by the battery of the device, including LDO power supply circuit, logic or operation circuit, switch control circuit, reset circuit, switch machine control chip, DC-DC power supply circuit, indicator light circuit and buzzer circuit, DC- The input end of the DC power supply circuit is connected to the device battery, the input end of the LDO power supply circuit is connected to the device battery, the output end of the LDO power supply circuit is electrically connected to the input end of the switch control circuit, and the first output end of the switch control circuit is connected to the logical OR operation The first input end of the circuit is connected, the first output end of the switch control circuit is also electrically connected with the reset port of the switch machine control chip through the reset circuit, and the second output end of the switch control circuit is electrically connected with an input and output port of the switch machine control chip. Connection, the second input terminal of the logic or operation circuit is connected with an input and output port of the switch machine control chip, the output of the logic or operation circuit is connected with the enabling terminal of the DC-DC power supply circuit, and the output terminal of the DC-DC power supply circuit They are respectively connected to the power supply end of the reset circuit and the power supply port of the switch control chip, and the input terminal of the indicator light circuit and the control terminal of the buzzer circuit are both electrically connected to an input and output port of the switch control chip. The input end of the indicator light circuit is also connected to the first input end of the logic or operation circuit. The power supply terminal of the buzzer circuit is connected to the output terminal of the DC-DC power supply circuit. The logic or operation circuit includes the first diode for realizing the OR gate function and the second diode for realizing the OR gate function, and the first and second diodes for realizing the OR gate function. The anode of the pole tube is electrically connected to an input and output port of the switch machine control chip to realize the OR gate function. The anode of the second diode is connected to the first output terminal of the switch control circuit to realize the OR gate function. The first diode and the The cathodes of the OR gate functioning second diodes are all connected to the enabling terminal of the DC-DC power supply circuit. The enabling terminal of the DC-DC power supply circuit is also grounded through the resistor R4. The switch control circuit includes a transistor U4, a resistor R10, a button K1, a resistor R9, a capacitor C9, a resistor R11, a resistor R12 and a capacitor C10, the first end of the button K1 is connected to the collector of the transistor U4, and the The second end of the button K1 is connected to the base of the transistor U4 through the resistor R10, the second end of the button K1 is also grounded through the resistor R9, the collector of the transistor U4 is connected to the output end of the LDO power supply circuit, and the transistor U4 The base is grounded through the capacitor C9, the emitter of the triode U4 is grounded through the resistor R11, the emitter of the triode U4 is respectively connected to the first input terminal of the logic or operation circuit, and the emitter of the triode U4 is connected to the switch control chip through the reset circuit. The reset port is electrically connected, the emitter of the transistor U4 is also connected to the first end of the resistor R12, the second end of the resistor R12 is grounded through the capacitor C10, and the second end of the resistor R12 is also electrically connected to an input and output port of the switch control chip . The reset circuit includes a resistor R14, a resistor R13, a capacitor C11, a capacitor C12 and a field effect transistor U6, the drain of the field effect transistor U6 is connected to the output terminal of the DC-DC power supply circuit through the resistor R14, and the gate of the field effect transistor U6 The emitter of the transistor U4 is connected through the resistor R13, the gate of the field effect transistor U6 is grounded through the capacitor C11, the source of the field effect transistor U6 is grounded, the drain of the field effect transistor U6 is grounded through the capacitor C12, and the drain of the field effect transistor U6 The pole is electrically connected with an input and output port of the switch machine control chip. In this embodiment, STM32F103C8T6 is used to represent other equivalent control chips as the switch control chip, the LDO power circuit uses the XC6202P332PR chip to represent a similar LDO power chip, and the DC-DC power circuit uses an MP1584DC-DC power chip to represent a similar DC-DC power chip. When the embodiment is used, as long as one of the switch control circuit or the switch control chip outputs a control signal, the DC-DC power supply chip can start to supply power. In this way, the switch control chip can be completely cut off when the machine is turned off. Electricity, and the utility model is provided with reset circuit, can forcibly make switch machine control chip reset by reset circuit, and using method is almost the same as existing switch circuit, but switch machine control chip can cut off power completely, thereby saves electric energy. Specifically, in this embodiment, when the button K1 is not pressed, the triode U4 is not turned on, and the output is at a continuous low level; when the button K1 is pressed, the triode U4 is turned on, and the output is at a continuous high level . When the triode U4 emits a very high level, the enabling terminal of the DC-DC power supply circuit is also high, and the DC-DC power supply circuit starts to work, and the output current supplies power to the reset circuit and the switch control chip. The power-on reset of the switch machine control chip outputs a high-level signal to the first input terminal of the logic or operation circuit to ensure that the enable terminal of the DC-DC power supply circuit is continuously high, so that the DC-DC power supply circuit is always in the working state. At this time Release the button K1 to complete the boot process. After starting up, when the button K1 is pressed again, the switch machine control chip will detect that the emitter of the transistor U4 changes from low level to high level, and at this time the switch machine control chip is powered on and resets to output a low level signal to the logic or The first input terminal of the operation circuit can be turned off. When shutting down, because the resistor R4 is pulled down to the ground, the DC-DC power supply circuit shuts down and has no output, until the enable terminal of the DC-DC power supply circuit is at a high level, the DC-DC power supply circuit outputs current to supply power to the switch machine control chip . The function of capacitor C9 in the switch control circuit is to debounce the button. The function of resistor R12 and capacitor C10 is to ensure that the signal passing through resistor R12 will have a certain delay, and the signal will be slower than the signal directly collected from the emitter of triode U4, ensuring There is no signal at the VDDA terminal of the switch machine control chip before power-on, and the resistor R14 and capacitor C12 in the reset circuit complete the reset action of the switch machine control chip at the moment of power-on. After starting up, the button K1 is released, the gate of the field effect transistor U6 is at a low level, the field effect transistor U6 is turned off, and the RESET terminal of the switch control chip is continuously at a high level. When there is a problem with the device program and the shutdown program cannot be executed, press the button K1 often, the gate of the field effect transistor U6 will change from low level to high level, and the capacitor C11 will be charged through the resistor R13. When the charging voltage reaches the open level of the field effect transistor U6 , the field effect transistor U6 is turned on, and the switching machine control chip changes from high level to low level, which can forcibly reset the switching machine control chip.

In the prior art, after shutdown, the switch control chip is still working, which inevitably consumes a part of the battery capacity; and in the above embodiments, after the shutdown, the DC-DC power supply circuit has no output, and the switch control chip is completely Power failure, that is, the power-on/off control chip does not consume battery capacity after power-off. At the same time, this solution realizes single-button power-on, power-off and reset operations, and has sound and indicator light prompt functions, which can prevent equipment users from misoperation.

Example 2

It is basically the same as Embodiment 1, except that the logic or operation circuit is an OR gate, and the first input end of the OR gate is electrically connected with an input and output port of the switch control chip, and the second input end of the OR gate is connected with the switch control chip. The first output terminal of the circuit is electrically connected, and the output terminal of the OR gate is connected with the enable terminal of the DC-DC power supply circuit.

The above-described embodiment is only a preferred solution of the utility model, and does not limit the utility model in any form. There are other variations and improvements without exceeding the technical solution described in the claims. type.

Claims (8)

1. A switch circuit, powered by a device battery, is characterized in that: it includes an LDO power circuit, a logic or operation circuit, a switch control circuit, a reset circuit, a switch control chip, a DC-DC power circuit, an indicator light circuit and a bee The buzzer circuit, the input end of the DC-DC power circuit is connected to the device battery, the input end of the LDO power circuit is connected to the device battery, the output end of the LDO power circuit is electrically connected to the input end of the switch control circuit, and the first switch control circuit The output end is connected with the first input end of the logical or operation circuit, the first output end of the switch control circuit is also electrically connected with the reset port of the switch machine control chip through the reset circuit, and the second output end of the switch control circuit is connected with the switch machine control chip One input and output port of the logic or operation circuit is electrically connected, the second input terminal of the logic or operation circuit is connected with an input and output port of the switch machine control chip, the output of the logic or operation circuit is connected with the enable terminal of the DC-DC power supply circuit, and the DC-DC power supply circuit is connected. The output terminal of the DC power supply circuit is respectively connected with the power supply terminal of the reset circuit and the power port of the switch control chip, and the input terminal of the indicator light circuit and the control terminal of the buzzer circuit are all connected with an input of the switch control chip. The output port is electrically connected. 2. The switch machine circuit according to claim 1, characterized in that: the input end of the indicator light circuit is also connected to the first input end of the logical OR operation circuit. 3. The switching machine circuit according to claim 1, characterized in that: the power supply end of the buzzer circuit is connected with the output end of the DC-DC power supply circuit, 4. The switching machine circuit according to claim 1, characterized in that: the logic or operation circuit is an OR gate, and the first input terminal of the OR gate is electrically connected with an input and output port of the switching machine control chip, and the second input terminal of the OR gate is electrically connected. The input terminal is electrically connected with the first output terminal of the switch control circuit, and the output terminal of the OR gate is connected with the enable terminal of the DC-DC power supply circuit. 5. The switching machine circuit according to claim 1, characterized in that: the logic or operation circuit includes a first diode for realizing the OR gate function and a second diode for realizing the OR gate function, and the first diode for realizing the OR gate function The anode of the tube is electrically connected to an input and output port of the switch machine control chip to realize the OR gate function. The anode of the second diode is connected to the first output end of the switch control circuit to realize the OR gate function. The cathodes of the second gate diodes are all connected to the enabling terminal of the DC-DC power supply circuit. 6. The switch machine circuit according to claim 4 or 5, characterized in that: the enabling terminal of the DC-DC power supply circuit is also grounded through a resistor R4. 7. The switch machine circuit according to claim 4 or 5, characterized in that: the switch control circuit includes a triode U4, a resistor R10, a button K1, a resistor R9, a capacitor C9, a resistor R11, a resistor R12 and a capacitor C10, the The first end of the button K1 is connected to the collector of the transistor U4, the second end of the button K1 is connected to the base of the transistor U4 through a resistor R10, and the second end of the button K1 is grounded through a resistor R9. The collector of the triode U4 is connected to the output terminal of the LDO power supply circuit, the base of the triode U4 is grounded through the capacitor C9, the emitter of the triode U4 is grounded through the resistor R11, and the emitter of the triode U4 is respectively connected to the first logic or operation circuit. Connected to the input terminal, the emitter of the transistor U4 is electrically connected to the reset port of the switch control chip through the reset circuit, the emitter of the transistor U4 is also connected to the first end of the resistor R12, the second end of the resistor R12 is grounded through the capacitor C10, and the resistor The second end of R12 is also electrically connected to an input and output port of the switch machine control chip. 8. The switching machine circuit according to claim 7, characterized in that: the reset circuit comprises a resistor R14, a resistor R13, a capacitor C11, a capacitor C12 and a field effect transistor U6, and the drain of the field effect transistor U6 is connected with the resistor R14. The output terminal of the DC-DC power supply circuit is connected, the gate of the field effect transistor U6 is connected to the emitter of the transistor U4 through the resistor R13, the gate of the field effect transistor U6 is grounded through the capacitor C11, the source of the field effect transistor U6 is grounded, and the field The drain of the effect transistor U6 is grounded through the capacitor C12, and the drain of the field effect transistor U6 is electrically connected to an input and output port of the switching machine control chip.