Power switch circuit

Abstract

A power switch circuit is at least provided with a voltage isolation unit, a control switching unit and a feedback unit, a power output end is used for outputting power to a vehicle lamp driving circuit, and the voltage isolation unit is connected with the power output end, so that when the power output end is short-circuited, the control switching unit is closed, and the feedback unit feeds back the power to the vehicle lamp driving circuit. And the voltage isolation unit is closed together so as to cut off a current loop of the vehicle lamp driving circuit.

Description

Technical Field

[0001] This utility model relates to a power switch circuit, and more particularly to a short-circuit protection controller for protecting vehicle lighting circuits from short circuits. Background Technology

[0002] LED technology is characterized by low power consumption, high efficiency, and excellent light color, so its application is becoming more and more widespread, especially in the field of automotive lighting.

[0003] However, LED lights are easily damaged due to factors such as the application environment and power supply voltage and current. Damage may cause short circuits, which can lead to problems such as overheating of wires, rapid battery drain, damage to electronic components, fire risks, and abnormalities in the vehicle's electrical system. This is a serious problem that needs to be addressed immediately, and taking appropriate measures in a timely manner can prevent further damage and safety hazards.

[0004] Therefore, short-circuit protection circuits are now widely used to protect LED lights. However, these LED short-circuit protection circuits in the existing technology have disadvantages such as complex structure, slow response, and high production cost, so they urgently need to be improved. Utility Model Content

[0005] Therefore, this utility model provides a power switch circuit that can stop supplying power to the vehicle light circuit when a short circuit occurs, and automatically restore the circuit after the short circuit problem is resolved, so that the circuit can continue to operate. Therefore, this utility model provides a better solution. The power switch circuit of this utility model includes: a power input terminal for providing an input voltage; a power output terminal connected to a vehicle light drive circuit; a voltage isolation unit connected to the power input terminal and the power output terminal, the voltage isolation unit for receiving the input voltage, and the voltage isolation unit can also output an output voltage to the power output terminal, and then output from the power output terminal to the vehicle light drive circuit; a control switching unit connected to the voltage isolation unit for starting or stopping the voltage isolation unit; and a feedback unit, one end of the feedback unit is connected to the control switching unit, and the other end of the feedback unit is connected to the power output terminal.

[0006] More specifically, the control switching unit is also connected in series with a control signal terminal, which can send a high-potential signal to the control switching unit to start the control switching unit.

[0007] More specifically, when the power output terminal is short-circuited to ground, the feedback unit is turned on to form a low potential and transmit it to the control switching unit to turn off the control switching unit.

[0008] More specifically, when the power output terminal is short-circuited to ground, the feedback unit is turned on and the control switching unit is turned off. When the control switching unit is turned off, the voltage isolation unit is also turned off, and the power output terminal stops outputting power to the vehicle light drive circuit. When the power output terminal returns to normal, the voltage of the feedback unit returns to normal, so that the control switching unit can operate normally. The voltage isolation unit is then activated by the control switching unit, so that the power output terminal can output power to the vehicle light drive circuit. Attached Figure Description

[0009] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0010] Figure 1 This is a schematic diagram of the overall connection of the power switch circuit of this utility model.

[0011] Figure 2 This is a schematic diagram of the power switch circuit architecture of this utility model.

[0012] Figure 3 This is a schematic diagram of the implementation circuit of the vehicle headlight drive circuit of the power switch circuit of this utility model.

[0013] Figure 4 This is a schematic diagram of the power switch circuit of this utility model.

[0014] Explanation of reference numerals in the attached figures

[0015] 1: Power switch circuit

[0016] 11: Power input terminal

[0017] 12: Power output terminal

[0018] 13: Voltage isolation unit

[0019] 14: Control Switching Unit

[0020] 15: Feedback Unit

[0021] 16: Control signal terminal

[0022] 2: Headlight drive circuit. Detailed Implementation

[0023] Other technical contents, features and effects of this utility model will be clearly presented in the following detailed description of the preferred embodiments with reference to the accompanying drawings.

[0024] Please see Figure 1 The figure shows an overall connection diagram of the power switch circuit of this utility model. As shown in the figure, the power switch circuit is connected to a vehicle light drive circuit 2.

[0025] The power switch circuit 1 is used in environments where the device is a circuit board or an electronic device with an internal circuit board.

[0026] like Figure 2 As shown, the power switch circuit 1 has a power input terminal 11, a power output terminal 12, a voltage isolation unit 13, a control switching unit 14, a feedback unit 15, and a control signal terminal 16.

[0027] The power input terminal 11 is used to provide an input voltage.

[0028] The power output terminal 12 is connected to the vehicle light drive circuit 2 to supply power to the vehicle light drive circuit 2.

[0029] The voltage isolation unit 13 is connected to the power input terminal 11 and the power output terminal 12. The voltage isolation unit 13 is used to receive the input voltage, and the voltage isolation unit 13 can also output an output voltage to the power output terminal 12, so that the power output terminal 12 can output to the vehicle lamp drive circuit 2.

[0030] The control switching unit 14 is connected to the voltage isolation unit 13 and is used to start or stop the voltage isolation unit 13.

[0031] The feedback unit 15 is connected at one end to the control switching unit 14 and at the other end to the power output terminal 12.

[0032] The control signal terminal 16 is connected to the control switching unit 14. The control signal terminal can send a high potential signal to the control switching unit 14 to start the control switching unit 14. The feedback unit 15 is connected between the power output terminal 12 and the control switching unit 14 to form a feedback loop.

[0033] like Figure 3 The figure shows the implementation circuit architecture of the vehicle headlight drive circuit 2. As shown in the figure, the vehicle headlight drive circuit 2 is connected to the power output terminal 12, where DL12, DL13, DL14, DL15, DL16, DL17, DL18, and DL20 are light-emitting diodes.

[0034] The vehicle light drive circuit 2 also includes current-limiting resistors RL32…RL38 and RL96. These current-limiting resistors are used to keep the vehicle light drive circuit 2 lit with a constant current. The vehicle light drive circuit 2 can be designed using a dedicated LED constant current IC, or it can be designed using a transistor or some voltage regulator IC.

[0035] like Figure 4 The diagram shows the implementation circuit architecture of this power switch circuit. The normal operating mechanism of the circuit is explained below:

[0036] (1) During normal operation, the control signal terminal 16 (HSDC, CPU control signal) will send a high signal, which will start the control switching unit 14 (QL6) and at the same time, the control switching unit 14 (QL6) will start the voltage isolation unit 13 (QL7).

[0037] (2) In this state, the power output terminal 12 (HSD_OUT) will maintain a constant voltage value, the power input terminal 11 will input a voltage (e.g. +12V) to the voltage isolation unit 13 (QL7), and the power output terminal 12 (HSD_OUT) will output a fixed voltage (e.g. +12V) to the vehicle lamp drive circuit 2 so that the vehicle lamp drive circuit 2 can work normally.

[0038] (3) In this state, the positive voltage of the feedback unit 15 (DL19) is +5 and the negative voltage is +12, so the feedback unit 15 (DL19) is in an open circuit state.

[0039] like Figure 4 The diagram shows the implementation circuit architecture of this power switch circuit. The short-circuit operation mechanism of this circuit is explained below:

[0040] (1) When the positive terminal of the vehicle light drive circuit 2 is short-circuited to the power supply, the power output terminal 12 (HSD_OUT) will be short-circuited and the ground voltage will be pulled down to 0V.

[0041] (2) In this state, the negative voltage of the feedback unit 15 (DL19) will be pulled down to +0.7V, which will enable the feedback unit 15 (DL19) to be turned on.

[0042] (3) Continuing from above, when the feedback unit 15 (DL19) is turned on, a low potential signal will be generated for the control switching unit 14 (QL6) so that the control switching unit 14 (QL6) is turned off and closed. At the same time, the voltage isolation unit 13 (QL7) will also be turned off and closed, thus automatically cutting off the current loop of the vehicle light drive circuit 2.

[0043] When the power short circuit of the headlight drive circuit 2 is removed, the voltage of the power output terminal 12 (HSD_OUT) will gradually rise, the feedback unit 15 (DL19) will return to the open circuit state, and the control switching unit 14 (QL6) and the voltage isolation unit 13 (QL7) will be able to restart and continue to output a fixed voltage to the headlight drive circuit 2 through the power output terminal 12 (HSD_OUT) so that the headlight drive circuit 2 can work normally.

[0044] The power switch circuit provided by this utility model has the following advantages compared with other existing technologies:

[0045] (1) This utility model provides a power switch circuit that can stop supplying power to the vehicle light circuit when a short circuit occurs, and the circuit can automatically recover after the short circuit problem is resolved so that the circuit can continue to operate.

[0046] (2) This utility model has the characteristics of simple circuit structure, timely response and low production cost.

[0047] (3) In addition to providing short circuit protection, this utility model can also provide short circuit protection for the positive and negative power supply of LED, effectively avoiding circuit burnout and misjudgment, and ensuring that LED products work reliably, normally and stably.

[0048] The present invention has been disclosed above through the above embodiments, but it is not intended to limit the present invention. Any person skilled in the art, after understanding the foregoing technical features and embodiments of the present invention, may make some modifications and refinements without departing from the protection scope of the present invention.

Claims

1. A power switch circuit, characterized in that, include: A power input terminal is used to provide an input voltage; One power output terminal is connected to a vehicle light drive circuit; A voltage isolation unit is connected to the power input terminal and the power output terminal. The voltage isolation unit is used to receive the input voltage, and the voltage isolation unit can also output an output voltage to the power output terminal, and then output the voltage from the power output terminal to the vehicle light drive circuit. A control switching unit is connected to the voltage isolation unit to start or stop the voltage isolation unit; as well as A feedback unit, one end of which is connected to the control switching unit, and the other end of which is connected to the power output terminal.

2. The power switch circuit as described in claim 1, characterized in that, The control switching unit is also connected in series with a control signal terminal, which can send a high-potential signal to the control switching unit to start the control switching unit.

3. The power switch circuit as described in claim 1, characterized in that, When the power output terminal is short-circuited to ground, the feedback unit is turned on to form a low potential and transmit it to the control switching unit to turn off the control switching unit.

4. The power switch circuit as described in claim 1, characterized in that, When the power output terminal is short-circuited to ground, the feedback unit is turned on and the control switching unit is turned off. When the control switching unit is turned off, the voltage isolation unit is also turned off, and the power output terminal stops outputting power to the vehicle headlight drive circuit. When the power output terminal returns to normal, the voltage of the feedback unit returns to normal, so that the control switching unit can operate normally. The voltage isolation unit is then activated by the control switching unit, so that the power output terminal can output power to the vehicle headlight drive circuit.

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