Dual-power control circuit

Abstract

The utility model relates to the technical field of switch power supply control, in particular to a dual power supply control circuit, which comprises a first power supply input end, a second power supply input end, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a diode D1, a voltage stabilizing diode D2, a voltage stabilizing diode D3, a diode D4, an optical coupler U1, an optical coupler U2, a switch tube Q1 and a switch tube Q2. The switch is ingenious in design and compact in structure, the input power supply supplies power according to conditions and priorities, the electric quantity of the battery cannot be consumed quickly, the switch is suitable for a scene in which the battery is used as a standby power supply, normal work of the switch is ensured, work stability is improved, and the service life is prolonged; it is ensured that key equipment or a system can stably operate when the main power source is available, meanwhile, when the main power source breaks down, the standby power source can be seamlessly switched, and the reliability and stability of the system are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of switch power control, in particular to a dual power supply control circuit. Background Art

[0002] At present, there are many types of switches on the market, but basically they all adopt a single power input design, which is basically fine in most scenarios. However, it is not suitable for harsh and complex environments (such as frequent lightning strikes, static electricity, and unstable voltage, which can easily cause power damage). Therefore, under such working conditions, most people will choose to use a dual power redundancy control circuit, that is, connect two power supplies. When one of them is damaged, the other power supply can supply power to the machine in time. However, this dual power supply circuit generally has no priority. Either the one with higher voltage is used for power supply, or both power supplies are supplied at the same time. However, this situation is very unsuitable for situations where the backup power supply is a battery. If the input power is supplied without priority, the battery power may be consumed quickly, and the normal operation of the switch cannot be guaranteed. Summary of the Invention

[0003] In response to the problems of the prior art, the utility model provides a dual-power supply control circuit with an ingenious design and a compact structure. The input power supply is prioritized according to different situations, and the battery power will not be consumed quickly. The utility model is suitable for scenarios where batteries are used as backup power supplies, ensuring the normal operation of the switch and improving the working stability and service life. It ensures that key equipment or systems can operate stably when the main power supply is available, and can seamlessly switch to the backup power supply when the main power supply fails, thereby improving the reliability and stability of the system.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The utility model provides a dual power supply control circuit, which includes a first power supply input terminal, a second power supply input terminal, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a diode D1, a voltage regulator diode D2, a voltage regulator diode D3, a diode D4, an optocoupler U1, an optocoupler U2, a switch tube Q1 and a switch tube Q2;

[0006] The V1+ terminal of the first power input terminal is respectively connected to one end of the resistor R1, one end of the resistor R2, and the anode of the Zener diode D2. The cathode of the Zener diode D2 is connected to the output terminal. The other end of the resistor R1 is connected to the positive electrode of the light-emitting diode in the optocoupler U2. The negative electrode of the light-emitting diode in the optocoupler U2 is connected to the V1- terminal of the first power input terminal.

[0007] The other end of the resistor R2 is respectively connected to the cathode of the diode D1, the gate of the switch tube Q1, and the collector of the transistor in the optocoupler U1. The drain of the switch tube Q1, the anode of the diode D1, and the emitter of the transistor in the optocoupler U1 are respectively connected to the V1- terminal of the first power input terminal. The source of the switch tube Q1 is grounded.

[0008] The V2+ terminal of the second power input terminal is respectively connected to one end of the resistor R3, one end of the resistor R4, and the anode of the Zener diode D3. The cathode of the Zener diode D3 is connected to the output terminal. The other end of the resistor R3 is connected to the positive electrode of the light-emitting diode in the optocoupler U1. The negative electrode of the light-emitting diode in the optocoupler U1 is connected to the V2- terminal of the second power input terminal.

[0009] The other end of the resistor R4 is respectively connected to the cathode of the diode D4, the gate of the switch tube Q2 and the collector of the transistor in the optocoupler U2. The drain of the switch Q2, the anode of the diode D4 and the emitter of the transistor in the optocoupler U2 are respectively connected to the V2- terminal of the second power supply input terminal. The source of the switch tube Q2 is grounded.

[0010] Preferably, the switch tube Q1 is an NMOS tube.

[0011] Preferably, the switch tube Q2 is an NMOS tube.

[0012] Beneficial effects of the utility model:

[0013] This utility model features an ingenious design and compact structure. The input power is prioritized based on specific situations, preventing rapid battery drain. It is suitable for use in scenarios where batteries are used as backup power sources, ensuring the normal operation of the switch and improving operational stability and service life. Specifically, the circuit of this utility model clearly defines and automatically prioritizes the two power sources. Under normal circumstances, the first power input is set as the primary power source, providing priority power. The second power input acts as a bypass or backup power source, automatically taking over power supply duties in the event of a primary power failure. This design ensures that critical equipment or systems can operate stably when the primary power source is available, while seamlessly switching to the backup power source in the event of a primary power failure, improving system reliability and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The utility model is a circuit diagram of a dual power supply control circuit. DETAILED DESCRIPTION

[0015] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with the embodiments and drawings. The contents mentioned in the embodiments are not intended to limit the present invention. The present invention is described in detail below in conjunction with the drawings.

[0016] In the embodiment of this application, Figure 1 As shown, a dual power supply control circuit includes a first power supply input terminal, a second power supply input terminal, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a diode D1, a voltage regulator diode D2, a voltage regulator diode D3, a diode D4, an optocoupler U1, an optocoupler U2, a switch tube Q1 and a switch tube Q2; the switch tube Q1 is an NMOS tube, and the switch tube Q2 is an NMOS tube;

[0017] The V1+ terminal of the first power input terminal is respectively connected to one end of the resistor R1, one end of the resistor R2, and the anode of the Zener diode D2. The cathode of the Zener diode D2 is connected to the output terminal. The other end of the resistor R1 is connected to the positive electrode of the light-emitting diode in the optocoupler U2. The negative electrode of the light-emitting diode in the optocoupler U2 is connected to the V1- terminal of the first power input terminal.

[0018] The other end of the resistor R2 is respectively connected to the cathode of the diode D1, the gate of the switch tube Q1, and the collector of the transistor in the optocoupler U1. The drain of the switch tube Q1, the anode of the diode D1, and the emitter of the transistor in the optocoupler U1 are respectively connected to the V1- terminal of the first power input terminal. The source of the switch tube Q1 is grounded.

[0019] The V2+ terminal of the second power input terminal is respectively connected to one end of the resistor R3, one end of the resistor R4, and the anode of the Zener diode D3. The cathode of the Zener diode D3 is connected to the output terminal. The other end of the resistor R3 is connected to the positive electrode of the light-emitting diode in the optocoupler U1. The negative electrode of the light-emitting diode in the optocoupler U1 is connected to the V2- terminal of the second power input terminal.

[0020] The other end of the resistor R4 is respectively connected to the cathode of the diode D4, the gate of the switch tube Q2 and the collector of the transistor in the optocoupler U2. The drain of the switch Q2, the anode of the diode D4 and the emitter of the transistor in the optocoupler U2 are respectively connected to the V2- terminal of the second power supply input terminal. The source of the switch tube Q2 is grounded.

[0021] Specifically, under the above setting, the implementation method of the embodiment of the present application is as follows: two input power supplies (a first power input terminal and a second power input terminal), if the first power input terminal is the main input power supply and the second power input terminal is the bypass input power supply, when the first power input terminal is powered first, the DC voltage and current will first pass through the resistor R2 in parallel with the main input power supply, and then pass through the 12V Zener diode D1 in parallel with the resistor R2. At the same time, a switch tube Q1 is also connected in parallel with the cathode of the Zener diode D1. The switch tube Q1 is responsible for controlling the output circuit of the first power input terminal. When the voltage passes through the resistor R2 and breaks down the Zener diode D1, the gate of the switch tube Q1 has a stable 12V voltage. At this time, the switch tube Q1 is turned on, the first power input terminal is turned on, and power supply starts;

[0022] At the same time, V1+ of the first power input terminal will reach the positive electrode of the light-emitting diode of the optocoupler U2 after passing through the resistor R1 to limit the current, and the negative electrode of the light-emitting diode of the optocoupler U2 is directly connected to the V1- terminal of the first power input terminal. After the voltage passes through the resistor R1, current is generated. At this time, the light-emitting diode inside the optocoupler U2 starts to emit light, driving the NPN transistor inside the optocoupler U2 to turn on (pins 3 and 4 of the optocoupler U2 in the figure), and directly pulling the gate voltage of the switch tube Q2 at the V2- terminal of the second power input terminal down to 0V. At this time, no matter how the voltage is passed through the second power input terminal, because the gate of the switch tube Q2 at the V2- terminal of the second power input terminal is pulled down to 0V, the switch tube Q2 cannot be turned on. At this time, when the first power input terminal is powered, the bypassed second power input terminal is not powered;

[0023] When the main power supply is changed to the second power input terminal, and the first power input terminal is used as a bypass power supply, the same applies. First, the second power input terminal is powered. After the second power input terminal is powered on, the light-emitting diode inside the optocoupler U1 is lit through the resistor R3 on the power path of the second power input terminal, so that the 3 and 4 pins of the optocoupler U1 are turned on, and the gate voltage of the switch tube Q1 that controls the first power input terminal V1- is pulled down. At this time, the V1- terminal of the first power input terminal cannot be powered because the control switch tube Q1 cannot be turned on.

[0024] The embodiment of the present application is cleverly designed and compact in structure. The input power is prioritized according to the situation, and the battery power will not be consumed quickly. It is suitable for scenarios where the battery is used as a backup power source, ensuring the normal operation of the switch and improving the working stability and service life. That is, the circuit of the embodiment of the present application can clearly define and automatically execute the priority of the two power sources; under normal circumstances, the first power source V1 (the first power input terminal) is set as the main power source and has priority power supply; while the second power source V2 (the second power input terminal) is used as a bypass or backup power source, automatically taking over the power supply task when the main power source fails; this design ensures that critical equipment or systems can operate stably when the main power source is available, and can seamlessly switch to the backup power source when the main power source fails, thereby improving the reliability and stability of the system.

[0025] In addition, in the embodiments of the present application, the circuit utilizes optocouplers (U1 and U2) as signal conversion and isolation elements to achieve automatic switching between power sources. When the main power supply V1 (the first power input) is operating normally, it provides current to the optocoupler U2 through resistor R1, turning on the NPN transistor inside the optocoupler U2. This in turn lowers the gate voltage of the control MOS transistor Q2 of the bypass power supply V2, preventing the second power input from supplying power. Conversely, when the second power input becomes the main power source, a similar mechanism controls the power supply to the first power input, enabling fast and accurate switching between power sources without external intervention.

[0026] Furthermore, in the embodiment of the present application, since NMOS tubes are used as switching elements in the circuit design, they have low on-resistance and fast switching speed, and thus can reduce energy consumption while ensuring current transmission efficiency; in addition, when one power supply is not supplying power, by lowering the gate voltage of the NMOS tube that controls it, it is ensured that the power supply does not consume electrical energy unnecessarily, thereby further improving the energy-saving effect of the entire power supply system.

[0027] When power is supplied from the first or second power input, the input voltage is limited and stabilized by a series resistor (R2 or R3) and a Zener diode (D1 or D2, assuming a similar arrangement is also used for the second power input). Zener diode D1 ensures a stable 12V voltage at the gate of switch Q1, reliably controlling its on / off state. This helps protect subsequent circuits from excessively high or low voltages, improving the circuit's anti-interference capabilities and service life.

[0028] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention is disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of the above-disclosed technical contents without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technology of the present invention, which do not depart from the content of the technical solution of the present invention, are within the scope of the technical solution of the present invention.

Claims

1. A dual power supply control circuit, characterized in that: It includes a first power input terminal, a second power input terminal, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a diode D1, a voltage-stabilizing diode D2, a voltage-stabilizing diode D3, a diode D4, an optocoupler U1, an optocoupler U2, a switch tube Q1, and a switch tube Q2; The V1+ terminal of the first power input terminal is respectively connected to one end of the resistor R1, one end of the resistor R2, and the anode of the Zener diode D2. The cathode of the Zener diode D2 is connected to the output terminal. The other end of the resistor R1 is connected to the positive electrode of the light-emitting diode in the optocoupler U2. The negative electrode of the light-emitting diode in the optocoupler U2 is connected to the V1- terminal of the first power input terminal. The other end of the resistor R2 is respectively connected to the cathode of the diode D1, the gate of the switch tube Q1, and the collector of the transistor in the optocoupler U1. The drain of the switch tube Q1, the anode of the diode D1, and the emitter of the transistor in the optocoupler U1 are respectively connected to the V1- terminal of the first power input terminal. The source of the switch tube Q1 is grounded. The V2+ terminal of the second power input terminal is respectively connected to one end of the resistor R3, one end of the resistor R4, and the anode of the Zener diode D3. The cathode of the Zener diode D3 is connected to the output terminal. The other end of the resistor R3 is connected to the positive electrode of the light-emitting diode in the optocoupler U1. The negative electrode of the light-emitting diode in the optocoupler U1 is connected to the V2- terminal of the second power input terminal. The other end of the resistor R4 is respectively connected to the cathode of the diode D4, the gate of the switch tube Q2 and the collector of the transistor in the optocoupler U2. The drain of the switch Q2, the anode of the diode D4 and the emitter of the transistor in the optocoupler U2 are respectively connected to the V2- terminal of the second power supply input terminal. The source of the switch tube Q2 is grounded.

2. The dual power supply control circuit according to claim 1, characterized in that: The switch tube Q1 is an NMOS tube.

3. The dual power supply control circuit according to claim 1, wherein: The switch tube Q2 is an NMOS tube.

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