Power supply protection circuit and liquid cooling system
By using NMOS, PMOS and PNP transistors in combination with resistors and Zener diodes for power supply protection circuits, the problems of complex or low reliability of power supply protection circuits in the prior art are solved, and simple and reliable overvoltage and reverse connection protection is achieved.
Patent Information
- Application Number
- CN202422712496.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-07
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2034-11-07
AI Technical Summary
Existing power supply protection circuits are complex or have low reliability, and cannot effectively prevent excessive power supply voltage from burning out subsequent circuits and reverse power supply connection from causing system malfunction.
Using NMOS, PMOS and PNP transistors with resistors and voltage regulator diodes, a simple power supply protection circuit is designed to achieve overvoltage and reverse connection protection.
The circuit architecture is simple and the reliability of overvoltage and reverse connection protection is high, which improves the stability and safety of the power supply system.
Smart Images
Figure CN223451619U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to power supply protection technical field, specifically is a power supply protection circuit and liquid cooling system. BACKGROUND
[0002] The reliability design of power supply is the prerequisite for ensuring the stable work of each electrical equipment and system. The power supply usually needs to prevent the burnout of the subsequent circuit caused by the excessively high power supply voltage and prevent the misoperation of the system caused by the reverse connection of the power supply. The liquid cooling system usually adopts 24V DC power supply. How to prevent the burnout of the subsequent circuit caused by the excessively high power supply voltage and prevent the misoperation of the system caused by the reverse connection of the power supply is the key link to ensure the reliability. The power supply protection circuit in the prior art is usually complex or has low reliability. SUMMARY
[0003] The utility model aims at providing a power supply protection circuit and liquid cooling system, which are used to solve the problem of complex or low reliability of the power supply protection circuit in the prior art.
[0004] The utility model solves the above problems through the following technical scheme:
[0005] A power supply protection circuit, comprising a resistor R2, the first end of the resistor R2 is connected with the positive pole of the power supply voltage, the first end of a resistor R1, the emitter of a triode Q2 and the source of a MOS tube Q3 respectively, the second end of the R2 is connected with the first end of a resistor R4 and the cathode of a Zener diode ZD2 respectively, the second end of the resistor R4 is connected with the first end of a capacitor C1 and the base of the triode Q2 respectively, the collector of the triode Q2 is connected with the second end of the capacitor C1, the first end of a resistor R5 and the first end of a resistor R6, the second end of the resistor R6 is connected with the gate of the MOS tube Q3, and the drain of the MOS tube Q3 is used as the positive end of voltage output and is connected with the first end of a resistor R3;
[0006] The second end of the resistor R1 is connected with the gate of a MOS tube Q1 and the cathode of a Zener diode ZD1 respectively, the anode of the Zener diode ZD1 and the Zener diode ZD2 is connected with the second end of the resistor R5, the second end of the resistor R3 and the source of the MOS tube Q1, and the drain of the MOS tube Q1 is connected with the negative pole of the power supply voltage, the second end of the resistor R3 is grounded and used as the negative end of voltage output.
[0007] Working principle:
[0008] When the supply voltage is normally input (i.e. the positive supply voltage), the voltage stabilizing diode ZD2 is cut off, the positive supply voltage is loaded to the base of the triode Q2 through the resistor R2 and the resistor R4, and the base voltage of the triode Q2 is equal to the supply voltage due to the direct current isolation of the capacitor C1, the emitter voltage of the triode Q2 is the supply voltage, the base-emitter voltage Vbe of the triode Q2 is 0V, and the triode Q2 is cut off.
[0009] When the supply voltage is overvoltage and the voltage stabilizing diode ZD2 is reversely broken down, the base voltage of the triode Q2 is clamped, the emitter of the triode Q2 is the overvoltage supply voltage, the base-emitter voltage Vbe of the triode Q2 is less than -0.7V, the triode Q2 is turned on, and then the overvoltage supply voltage is loaded to the gate of the MOS tube Q3 through the turned-on triode Q2 and the resistor R6, and the gate-source voltage Vgs of the MOS tube Q3 is 0V due to the small voltage drop of the triode Q2, so that the MOS tube Q3 is cut off and no voltage is output to the subsequent circuit, i.e. the overvoltage shutdown protection of the supply is realized.
[0010] When the positive supply voltage and the negative supply voltage are connected reversely, the negative supply voltage is loaded to the gate of the MOS tube Q1 through the resistor R1, the source of the MOS tube Q1 is grounded, so that the gate-source voltage Vgs of the MOS tube Q1 is 0V, the MOS tube Q1 is cut off, i.e. the MOS tube Q1 cuts off the ground network, no voltage is output to the subsequent circuit, and the reverse connection protection of the supply is realized.
[0011] As a further improvement of the utility model, the MOS tube Q3 is a PMOS tube.
[0012] As a further improvement of the utility model, the MOS tube Q1 is an NMOS tube.
[0013] As a further improvement of the utility model, the triode Q2 is a PNP type triode.
[0014] A liquid cooling system comprises the power supply protection circuit according to any one of the above.
[0015] Compared with the prior art, the utility model has the following advantages and beneficial effects:
[0016] The utility model skillfully utilizes one NMOS, one PMOS and one PNP type triode as main element, carries some resistance and voltage stabilizing diode element, namely realizes overvoltage and anti-reverse connection protection function, circuit architecture is simple, and reliability is high, has higher practicality and popularization value. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 The utility model discloses a circuit principle diagram. DETAILED DESCRIPTION
[0018] The utility model will be further explained in detail in connection with the embodiment, and the embodiment of the utility model is not limited to this.
[0019] Example 1:
[0020] Combining the accompanying Figure 1 Fig. 1 shows a power supply protection circuit, including resistance R2, the first end of resistance R2 is connected with power supply voltage positive pole, the first end of resistance R1, the emitter of triode Q2 and the source of MOS tube Q3 respectively, the second end of R2 is connected with the first end of resistance R4 and the cathode of voltage stabilizing diode ZD2 respectively, the second end of resistance R4 is connected with the first end of capacitor C1 and the base of triode Q2 respectively, the collector of triode Q2 is connected with the second end of capacitor C1, the first end of resistance R5 and the first end of resistance R6, the second end of resistance R6 is connected with the gate of MOS tube Q3, and the drain of MOS tube Q3 is connected with the first end of resistance R3 as voltage output positive end;
[0021] The second end of resistance R1 is connected with the gate of MOS tube Q1 and the cathode of voltage stabilizing diode ZD1 respectively, the anode of voltage stabilizing diode ZD1 and voltage stabilizing diode ZD2 is connected with the second end of resistance R5, the second end of resistance R3 and the source of MOS tube Q1, and the drain of MOS tube Q1 is connected with power supply voltage negative pole, and the second end of resistance R3 is grounded and connected with voltage output negative end.
[0022] Working principle:
[0023] When the VCC normal input (i.e. VCC+ = 24V) without overvoltage, the voltage stabilizing diode ZD2 is cut off (the working voltage of the voltage stabilizing diode is 28V), VCC+ is loaded to the base of the PNP type triode Q2 through the resistor R2 and the resistor R4, and the base voltage of the triode Q2 is VCC+ due to the direct current isolation of the capacitor C1, the emitter voltage of the triode Q2 is the input voltage VCC+, the Vbe of the triode Q2 is 0V, and the triode Q2 is cut off. The gate of the PMOS Q3 is grounded through the resistor R6 and the resistor R5, the source of the PMOS Q3 is VCC+, the Vgs of the PMOS Q3 is <0, the PMOS Q3 is turned on, VCC+ is normally output to the subsequent circuit through the PMOS Q3, and the output voltage 24V is obtained;
[0024] When the VCC+ voltage reaches 25.7V or above, the voltage stabilizing diode ZD2 is reversely broken down, the base voltage of the PNP type triode Q2 is clamped to 25V, the emitter of the triode Q2 is the overvoltage VCC+, and thus the Vbe of the PNP type triode Q2 is <-0.7V, the triode Q2 is turned on, and then the overvoltage VCC is loaded to the gate of the PMOS Q3 through the turned-on triode Q2 and the resistor R6, and since the turn-on voltage drop of the triode Q2 is very small, the Vgs of the PMOS Q3 can be approximately considered as 0V, Q3 is cut off, and no voltage is output to the subsequent circuit, i.e. the overvoltage shutdown protection of the VCC power supply is realized.
[0025] When the VCC+ and VCC- are connected reversely, VCC- is loaded to the gate of the NMOS Q1 through the resistor R1, the source of the NMOS Q1 is grounded, thus the Vgs of the NMOS Q1 is 0V, the NMOS Q1 is cut off, i.e. the NMOS Q1 cuts off the ground network, no voltage is output to the subsequent circuit, and the VCC reverse connection protection is realized.
[0026] Embodiment 2:
[0027] A liquid cooling system comprising a power supply protection circuit as described above.
[0028] Although the present application has been described with reference to the explanatory embodiments thereof, the above embodiments are merely the preferable embodiments of the present application, and the embodiments of the present application are not limited to the above embodiments, and it should be understood that many other modifications and embodiments can be designed by those skilled in the art, and these modifications and embodiments will fall within the scope and spirit of the present application.
Claims
1. A power supply protection circuit, characterized in that: It includes a resistor R2, wherein a first end of the resistor R2 is respectively connected to the positive electrode of the power supply voltage, the first end of the resistor R1, the emitter of the transistor Q2, and the source of the MOS transistor Q3; a second end of the resistor R2 is respectively connected to the first end of the resistor R4 and the cathode of the voltage-stabilizing diode ZD2; a second end of the resistor R4 is respectively connected to the first end of the capacitor C1 and the base of the transistor Q2; a collector of the transistor Q2 is connected to the second end of the capacitor C1, the first end of the resistor R5, and the first end of the resistor R6; a second end of the resistor R6 is connected to the gate of the MOS transistor Q3; and a drain of the MOS transistor Q3 serves as a voltage output positive terminal and is connected to the first end of the resistor R3; The second end of the resistor R1 is connected to the gate of the MOS transistor Q1 and the cathode of the Zener diode ZD1, respectively. The anodes of the Zener diodes ZD1 and ZD2 are connected to the second end of the resistor R5, the second end of the resistor R3, and the source of the MOS transistor Q1. The drain of the MOS transistor Q1 is connected to the negative electrode of the power supply voltage. The second end of the resistor R3 is grounded and serves as the negative voltage output terminal.
2. A power supply protection circuit according to claim 1, characterized in that: The MOS transistor Q3 is a PMOS transistor.
3. The power supply protection circuit according to claim 1, characterized in that: The MOS transistor Q1 is an NMOS transistor.
4. The power supply protection circuit according to claim 1, characterized in that: The transistor Q2 is a PNP transistor.
5. A liquid cooling system, characterized in that: The invention comprises a power supply protection circuit as described in any one of claims 1 to 4.