Simple undervoltage and overcurrent automatic charging control circuit

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A technical big cow originally created a control circuit design for automatic charging, which has excellent characteristics of undervoltage, overcurrent and automatic. Flexible control of the charging process with good security. If you are interested, you can verify it yourself. If you have good suggestions, please come up and discuss together.

I made a simple circuit and I don't know if I can work.


The 9V and 5V voltages are used for 7809 and 7805, and this circuit is used for 12V batteries.

1. Adjust R4 so that the battery output voltage is high at 10.5V, the inverter stops and locks up. The charger starts and self-locks.
2. Adjust R31 to make the inverter resume operation when the battery voltage is 12.5V, to prevent the inverter from working after the power is not fully charged and the power is off.

3. Adjust R28 so that the battery voltage stops at 14.5V.

4, adjust R22, so that the 8-pin voltage is 0.3V, protection when over-current. D23 is wrong, D23 should be stringed at 8 feet. 10 feet to ground and a 1K resistor and a 1UF capacitor.