CN219086789U - Vehicle-mounted USB power supply protection circuit - Google Patents

Abstract

The present disclosure relates to a vehicle-mounted USB power protection circuit, comprising: the device comprises a control module, an overvoltage protection module and a short-circuit protection module, wherein the control module is connected with the overvoltage protection module; the overvoltage protection module is connected with the control module and the short-circuit protection module. The protection circuit is built by utilizing the separation components, so that the short-circuit protection of the USB output power port to the vehicle-mounted battery and the vehicle body ground can be effectively solved, and meanwhile, the circuit greatly reduces the cost of the components and complex logic operation, and is a preferred mass production scheme.

Description

Vehicle-mounted USB power supply protection circuit

Technical Field

The disclosure relates to the technical field of automotive electronics, in particular to a vehicle-mounted USB power supply protection circuit.

Background

Along with the intelligent development of automobiles, a vehicle-mounted USB interface becomes an indispensable part of an automobile, people can use the USB interface to charge electronic equipment such as a mobile phone and the like, power can be supplied to an automobile data recorder, an intelligent OBD, an air purifier and the like, a USB power supply is generally provided by a power supply IC of a main circuit, meanwhile, if a USB power supply end is exposed outside, the USB power supply end is short-circuited with a vehicle battery or grounded under the unexpected condition, the USB current is overlarge, the damage of the vehicle-mounted equipment is caused, the damage of the vehicle-mounted equipment is avoided, a special protection chip is generally used for protecting the situation, but the hardware cost is increased to a certain extent, the control logic is complex, and the protection circuit is built by utilizing a discrete element, so that the short-circuit protection of the USB output end to the power supply and the ground can be effectively solved.

Disclosure of Invention

An object of the present disclosure is to provide a vehicle-mounted USB power protection circuit, including: the control module, the overvoltage protection module and the short-circuit protection module, wherein,

the control module is connected with the overvoltage protection module;

the overvoltage protection module is connected with the control module and the short-circuit protection module.

In one of the alternative embodiments, the system further comprises an anti-reflection module, a control module, an overvoltage protection module and a short-circuit protection module, wherein,

the anti-reverse module is connected with an input power supply, a control module and the overvoltage protection module;

in one alternative embodiment, the anti-back module includes a MOS transistor Q1.

In one alternative embodiment, the control module includes: resistor R1, resistor R3, transistor Q3,

the resistor R1 is connected with the resistor R3, the collector electrode of the triode Q3 is connected with the other end of the resistor R3, the emitter electrode of the triode Q3 is grounded, and the base electrode of the triode Q3 is connected with the overvoltage protection module.

In one alternative embodiment, the overvoltage protection module includes a diode D1, a resistor R4, and a resistor R8, where the resistor R4 is connected to the diode D1, the control module and the resistor R8, and the other end of the resistor R8 is grounded, and the diode D1 is further connected to the anti-reflection module and the short-circuit protection module.

In one alternative embodiment, the short-circuit protection module comprises a resistor R6, a triode Q4, a resistor R5, a resistor R2, a MOS transistor Q2,

the resistor R2 is connected with the resistor R5, the grid electrode of the MOS tube Q2 is connected, the resistor R5 is connected with the collector electrode of the triode Q4, the emitting stage of the triode Q4 is grounded, the base electrode of the triode Q4 is connected with the resistor R6, and the resistor R6 is connected with the drain electrode of the MOS tube Q2 and the external Vout.

The protection circuit is built by utilizing the separation components, so that the short-circuit protection of the USB output power port to the vehicle-mounted battery and the vehicle body ground can be effectively solved, and meanwhile, the circuit greatly reduces the cost of the components and complex logic operation, and is a preferred mass production scheme.

Additional features and advantages of the present disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification, illustrate the disclosure and together with the description serve to explain, but do not limit the disclosure. In the drawings:

fig. 1 is a circuit diagram of a vehicle-mounted USB power protection circuit provided according to an embodiment of the present application.

Description of the embodiments

Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the disclosure, are not intended to limit the disclosure.

Referring to fig. 1, in one embodiment of the present application, there is provided a vehicle-mounted USB power protection circuit, including: the device comprises a control module 100, an overvoltage protection module 200 and a short-circuit protection module 300, wherein the control module 100 is connected with the overvoltage protection module 200; the overvoltage protection module 200 connects the control module 100 and the short-circuit protection module 300.

With continued reference to fig. 1, in one alternative embodiment, the system further includes an anti-reflection module 400, where the anti-reflection module 400 is connected to the control module 100, the overvoltage protection module 200, and the short-circuit protection module 300, and the anti-reflection module 200 is connected to an input power source, the control module, and the overvoltage protection module. In one alternative embodiment, the anti-back module includes a MOS transistor Q1.

With continued reference to FIG. 1, in one of the alternative embodiments, the control module 100 includes: the device comprises a resistor R1, a resistor R3 and a triode Q3, wherein the resistor R1 is connected with the resistor R3, a collector electrode of the triode Q3 is connected with the other end of the resistor R3, an emitting stage of the triode Q3 is grounded, and a base electrode of the triode Q3 is connected with the overvoltage protection module.

With continued reference to fig. 1, in one alternative embodiment, the overvoltage protection module 200 includes a diode D1, a resistor R4, and a resistor R8, where the resistor R4 is connected to the diode D1, the control module and the resistor R8, and the other end of the resistor R8 is grounded, and the diode D1 is further connected to the anti-reflection module and the short-circuit protection module.

With continued reference to fig. 1, in one alternative embodiment, the short-circuit protection module 300 includes a resistor R6, a triode Q4, a resistor R5, a resistor R2, a MOS transistor Q2, where the resistor R2 is connected to the resistor R5, a gate of the MOS transistor Q2 is connected to the resistor R5, a collector of the triode Q4 is connected to the resistor R5, an emitter of the triode Q4 is grounded, a base of the triode Q4 is connected to the resistor R6, and the resistor R6 is connected to a drain of the MOS transistor Q2 and an external Vout.

The implementation forms of the modules in the above embodiments may be implemented independently, or may be implemented in combination. An embodiment of the present application fully adopts the circuit structure of each module, and the specific composition and connection manner are as follows: MOS pipe Q1 source and voltage VCC1 are connected, MOS pipe Q1's grid and resistance R1 and R3 be connected, R1 and voltage VCC2 be connected, R3 and triode Q3's collecting electrode link to each other, Q3's emitter ground, Q3's base link to each other with resistance R8, resistance R8 and GND are connected, R4 and zener diode D1 be connected, D1 and MOS pipe Q1's drain electrode and Q2's source link to each other, MOS pipe Q2's source and resistance R2 be connected, resistance R2 and resistance R5 and MOS pipe Q2's grid link to each other, resistance R5 and triode Q4's collecting electrode link to each other, Q4's emitter ground, triode Q4's base be connected with resistance R6, R6 and R7 and Q2's drain electrode and be connected with outside Vout, resistance R7 and diode D2 be connected, diode D2 and voltage VCC1 be connected.

In this case, the protection of the USB power supply ground works as follows:

VCC1 is used as positive voltage input, GND is ground, VCC2 is an enable signal, and VOUT is output voltage; 1. when the voltage U1 is input into the VCC1, the VCC2 enables the high level, the voltage of the grid electrode and the source electrode of the MOS tube Q1 is increased, so that the source electrode and the drain electrode of the MOS tube are conducted, the VCC1 conducts the collector electrode and the transmitter of the triode Q4 according to the voltage division condition of the Rload and the R7, and at the moment, the grid voltage of the MOS tube is the bottom, so that the source electrode and the drain electrode of the MOS tube Q2 are conducted.

Specifically, when VOUT is over-voltage, the gate and the source of the MOS transistor Q2 in the initial state are turned on, the drain and the source are turned on, the post-stage zener diode D1 breaks down, so that be of Q3 is turned on, ce is turned on, and at this time, the gate and the source of Q1 are turned off, and the drain and the source are turned off, so that Q1 is turned off, and VOUT voltage cannot flow backward to VCC1;

conversely, when VOUT and GND are connected, the base of the triode Q4 is at low level, which causes the collector and emitter of the triode Q4 to be turned on, and the gate of the further MOS transistor Q2 is at high level, which causes the source and drain of the MOS transistor Q2 to be turned off, so that the whole link is turned off, and VCC1 is protected from flowing to VOUT;

the interface short circuit relates to the condition that when the external VOUT and GND generate circuit, the collector and the emitter of the triode Q3 are not conducted, and similarly, the collector and the emitter of the triode Q4 are not conducted, so that the source electrode and the drain electrode of the MOS tube Q2 are turned off, and the switch of the VCC1 and the rear stage VOUT is protected to be turned off.

The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings, but the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solutions of the present disclosure within the scope of the technical concept of the present disclosure, and all the simple modifications belong to the protection scope of the present disclosure.

In addition, the specific features described in the above embodiments may be combined in any suitable manner without contradiction. The various possible combinations are not described further in this disclosure in order to avoid unnecessary repetition.

Moreover, any combination between the various embodiments of the present disclosure is possible as long as it does not depart from the spirit of the present disclosure, which should also be construed as the disclosure of the present disclosure.

Claims (6)

1. A vehicle-mounted USB power protection circuit, comprising: the control module, the overvoltage protection module and the short-circuit protection module, wherein,

the control module is connected with the overvoltage protection module;

the overvoltage protection module is connected with the control module and the short-circuit protection module.

2. The protection circuit of claim 1, further comprising an anti-reflection module, a control module, an overvoltage protection module, and a short circuit protection module, wherein,

the anti-reverse module is connected with an input power supply, the control module and the overvoltage protection module.

3. The protection circuit of claim 2, wherein the anti-reverse module comprises a MOS transistor Q1.

4. The protection circuit of claim 1, wherein the control module comprises: resistor R1, resistor R3, transistor Q3,

the resistor R1 is connected with the resistor R3, the collector electrode of the triode Q3 is connected with the other end of the resistor R3, the emitter electrode of the triode Q3 is grounded, and the base electrode of the triode Q3 is connected with the overvoltage protection module.

5. The protection circuit according to claim 2, wherein the overvoltage protection module comprises a diode D1, a resistor R4 and a resistor R8, the resistor R4 is connected to the diode D1, the control module and the resistor R8, the other end of the resistor R8 is grounded, and the diode D1 is further connected to the anti-reflection module and the short-circuit protection module.

6. The protection circuit according to claim 1, wherein the short-circuit protection module comprises a resistor R6, a triode Q4, a resistor R5, a resistor R2, a MOS transistor Q2,

the resistor R2 is connected with the resistor R5, the grid electrode of the MOS tube Q2 is connected, the resistor R5 is connected with the collector electrode of the triode Q4, the emitting stage of the triode Q4 is grounded, the base electrode of the triode Q4 is connected with the resistor R6, and the resistor R6 is connected with the drain electrode of the MOS tube Q2 and the external Vout.

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