Power supply polarity automatic correction conversion circuit

Abstract

The utility model discloses a power supply polarity automatic correction conversion circuit comprising a first NMOS tube, a second NMOS tube, a first PMOS tube, a second PMOS tube, a first input end, a second input end, a positive electrode output end and a negative electrode output end. The grid electrode of the first NMOS tube is connected with the second input end, the source electrode is connected with the negative output end, and the drain electrode is connected with the first input end; the grid electrode of the second NMOS tube is connected with the first input end, the source electrode is connected with the negative output end, and the drain electrode is connected with the second input end; a grid electrode of the first P MOS tube is connected with the second input end, a source electrode is connected with the positive electrode output end, and a drain electrode is connected with the first input end; the grid electrode of the second PMOS tube is connected with the first input end, the source electrode is connected with the positive output end, and the drain electrode is connected with the second input end. The circuit can be connected with positive and negative electrodes of a direct-current power supply at will, and is low in power consumption and voltage drop.

Description

Technical Field

[0001] The utility model belongs to the technical field of electronic circuits, and in particular relates to a power supply polarity automatic correction conversion circuit. Background Art

[0002] When an electronic device draws power from a DC power supply, the connection between the electronic device and the DC power supply must be strictly connected according to the positive and negative polarity, that is, the positive terminal of the electronic device is connected to the positive terminal of the DC power supply, and the negative terminal of the electronic device is connected to the negative terminal of the DC power supply.

[0003] To prevent damage to the DC power supply and / or electronic equipment due to reverse polarity during operation, the current technology uses a rectifier bridge with diodes between the DC power supply and the electronic device. This bridge inverts the DC power supply's output polarity, thus preventing reverse polarity. However, the diodes in the rectifier bridge exhibit significant losses during operation, increasing the power consumption of the entire circuit and reducing the operating voltage of the electronic device. Summary of the Invention

[0004] Purpose of the invention: In order to solve the problem in the prior art that electronic equipment uses a rectifier bridge when connected to a DC power supply to avoid large power consumption waste caused by reverse polarity, the utility model provides a power supply polarity automatic correction conversion circuit.

[0005] Technical solution: A power polarity automatic correction conversion circuit is connected between a DC power supply and an electronic device, comprising a first NMOS transistor, a second NMOS transistor, a first PMOS transistor, a second PMOS transistor, a first input terminal, a second input terminal, a positive output terminal, and a negative output terminal;

[0006] The gate of the first NMOS transistor is connected to the second input terminal, the source is connected to the negative output terminal, and the drain is connected to the first input terminal;

[0007] The gate of the second NMOS transistor is connected to the first input terminal, the source is connected to the negative output terminal, and the drain is connected to the second input terminal;

[0008] The gate of the first P MOS transistor is connected to the second input terminal, the source is connected to the positive output terminal, and the drain is connected to the first input terminal;

[0009] The gate of the second PMOS tube is connected to the first input terminal, the source is connected to the positive output terminal, and the drain is connected to the second input terminal.

[0010] Furthermore, the first NMOS transistor is the same as the second NMOS transistor.

[0011] Furthermore, the first PMOS transistor is the same as the second PMOS transistor.

[0012] Furthermore, the first input terminal and the second input terminal are used to connect to a DC power supply, regardless of positive or negative polarity.

[0013] Furthermore, the positive output terminal is used to connect to the positive power supply terminal of the electronic device, and the negative output terminal is used to connect to the negative power supply terminal of the electronic device.

[0014] Furthermore, the electronic device is a rechargeable battery.

[0015] Compared with the prior art, the present invention provides a power polarity automatic correction conversion circuit, so that the connection between the DC power supply and the electronic device can be arbitrary and is not restricted by the positive and negative poles; and because the automatic correction conversion circuit only contains MOS tubes, the internal resistance of the body diode of the MOS tube is small, and the loss after conduction is small, which reduces the power consumption of the entire circuit; the voltage drop it produces is small, and the impact on the power supply of the electronic equipment is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural diagram of the power polarity automatic correction conversion circuit. DETAILED DESCRIPTION

[0017] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments.

[0018] A power polarity automatic correction conversion circuit is connected between a DC power supply and an electronic device, and includes a first NMOS transistor Q3, a second NMOS transistor Q4, a first PMOS transistor Q2, a second PMOS transistor Q1, a first input terminal Vin1, a second input terminal Vin2, a positive output terminal Vout, and a negative output terminal GND.

[0019] The first input terminal Vin1 and the second input terminal Vin2 are used to connect to a DC power supply, regardless of positive or negative pole. That is, when in use, the first input terminal Vin1 can be connected to the positive pole of the DC power supply, and the second input terminal Vin2 can be connected to the negative pole of the DC power supply, or the first input terminal Vin1 can be connected to the negative pole of the DC power supply, and the second input terminal Vin2 can be connected to the positive pole of the DC power supply.

[0020] The positive output terminal Vout is used to connect to the positive power supply terminal of the electronic device, and the negative output terminal GND is used to connect to the negative power supply terminal of the electronic device. The electronic device can be a rechargeable battery or other electronic device that requires a DC power supply.

[0021] The gate of the first NMOS transistor Q3 is connected to the second input terminal Vin2, the source is connected to the negative output terminal GND, and the drain is connected to the first input terminal Vin1;

[0022] The gate of the second NMOS transistor Q4 is connected to the first input terminal Vin1, the source is connected to the negative output terminal GND, and the drain is connected to the second input terminal Vin2;

[0023] The gate of the first PMOS transistor Q2 is connected to the second input terminal Vin2, the source is connected to the positive output terminal Vout, and the drain is connected to the first input terminal Vin1;

[0024] The gate of the second PMOS transistor Q1 is connected to the first input terminal Vin1 , the source is connected to the positive output terminal Vout, and the drain is connected to the second input terminal Vin2 .

[0025] The first NMOS transistor is the same as the second NMOS transistor.

[0026] The first PMOS transistor is the same as the second PMOS transistor.

[0027] like Figure 1 This is a schematic diagram of the structure of the power polarity automatic correction conversion circuit, which shows the first working condition of the circuit connected to the DC power supply, that is, the first input terminal Vin1 is connected to the positive pole of the DC power supply, and the second input terminal Vin2 is connected to the negative pole of the DC power supply. At this time, the gate voltage of the first NMOS transistor Q3 is negative, and the gate voltage of the second NMOS transistor Q4 is positive; the gate voltage of the first PMOS transistor Q1 is negative, and the gate voltage of the second PMOS transistor Q2 is positive. In this case, the second NMOS transistor Q4 and the first PMOS transistor Q1 are turned on. Figure 1 As shown, the positive output terminal will be connected to the positive electrode of the DC power supply through the first PMOS transistor Q1. Equivalently, the positive output terminal is connected to the positive electrode of the DC power supply through the body diode in the first PMOS transistor Q1. Similarly, the negative output terminal will be connected to the negative electrode of the DC power supply through the second NMOS transistor Q4. Equivalently, the negative output terminal is connected to the positive electrode of the DC power supply through the body diode in the second NMOS transistor Q4. As can be seen from the above, on the one hand, the positive output terminal is connected to the positive electrode of the DC power supply, and the negative output terminal is connected to the negative electrode of the DC power supply, and thus can be connected to the positive and negative electrodes of the light source respectively. On the other hand, the positive or negative output terminal is only connected to the positive or negative electrode of the DC power supply through the body diode of the MOS transistor. The internal resistance of the body diode is generally tens of milliohms, so the loss after conduction is extremely small, and the voltage across the input terminal and the voltage across the output terminal of the power polarity conversion circuit remain substantially unchanged.

[0028] Accordingly, in the second operating condition of the automatic power polarity correction conversion circuit connected to the DC power supply, the first input terminal Vin1 is connected to the negative terminal of the DC power supply, and the second input terminal Vin2 is connected to the positive terminal of the DC power supply. In this case, the gate voltage of the second NMOS transistor Q4 is negative, while the gate voltage of the first NMOS transistor Q3 is positive; the gate voltage of the second PMOS transistor Q2 is negative, while the gate voltage of the first PMOS transistor Q1 is positive. In this condition, the first NMOS transistor Q3 and the second PMOS transistor Q2 are conductive. The positive output terminal is connected to the positive terminal of the DC power supply through the second PMOS transistor Q2. Equivalently, the positive output terminal is connected to the positive terminal of the DC power supply through the body diode within the second PMOS transistor Q2. Similarly, the negative output terminal is connected to the negative terminal of the DC power supply through the first NMOS transistor Q3. Equivalently, the negative output terminal is connected to the positive terminal of the DC power supply through the body diode within the first NMOS transistor Q3.

Claims

1. A power polarity automatic correction conversion circuit, characterized in that: Connected between a DC power supply and an electronic device, comprising a first NMOS transistor, a second NMOS transistor, a first PMOS transistor, a second PMOS transistor, a first input terminal, a second input terminal, a positive output terminal, and a negative output terminal; The gate of the first NMOS transistor is connected to the second input terminal, the source is connected to the negative output terminal, and the drain is connected to the first input terminal; The gate of the second NMOS transistor is connected to the first input terminal, the source is connected to the negative output terminal, and the drain is connected to the second input terminal; The gate of the first P MOS transistor is connected to the second input terminal, the source is connected to the positive output terminal, and the drain is connected to the first input terminal; The gate of the second PMOS tube is connected to the first input terminal, the source is connected to the positive output terminal, and the drain is connected to the second input terminal.

2. The power polarity automatic correction conversion circuit according to claim 1, characterized in that: The first NMOS transistor is the same as the second NMOS transistor.

3. The power polarity automatic correction conversion circuit according to claim 1 or 2, characterized in that: The first PMOS transistor is the same as the second PMOS transistor.

4. The power polarity automatic correction conversion circuit according to claim 1 or 2, characterized in that: The first input terminal and the second input terminal are used to connect a DC power supply, regardless of positive or negative polarity.

5. The power polarity automatic correction conversion circuit according to claim 1 or 2, characterized in that: The positive output terminal is used to connect to the positive power supply terminal of the electronic device, and the negative output terminal is used to connect to the negative power supply terminal of the electronic device.

6. The power polarity automatic correction conversion circuit according to claim 1 or 2, characterized in that: The electronic device is a rechargeable battery.

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