on video High precision 18650 battery charging circuit KIA7042AP

 High precision 18650 battery charging circuit KIA7042AP

  using this circuit you can use 1S and 2S 3.7 volt batteries. You can charge it easily and safely. The only thing you need to pay attention to is setting the calibration correctly. Set it to cut off the 4.2 volt output for 1S, hence the 8.4 volt output for 2S. and that's it, you can start using it. If you are not yet a subscriber, you need to subscribe now.

3.7v battery charger circuit with auto cut off

3.7v battery charger circuit diagram

3.7 volt battery charger automatic

Automatic 3.7 volt battery charger circuit

18650 battery charger with auto cutoff

3.7v battery full charge indicator

3.7v battery protection circuit

In this video i'm showing how to make 3.7 volt battery charger circuit with auto cut off on Full Charge.

For that i used TL431 Shunt Regulator, it's actually an adjustable zener.

I used mosfet which remains on by supplying small positive voltage using 1k resistor.

And cut off voltage is set at reference pin1 of TL431 by using resistors from both positive & negative.

When voltage in circuit reaches to threshold point TL431 connects negative voltage from pin2 to pin3 so positive voltage at mosfet gate pin becomes zero and Mosfet turns off.

 High precision 18650 battery charging circuit KIA7042AP

  using this circuit you can use 1S and 2S 3.7 volt batteries. You can charge it easily and safely. The only thing you need to pay attention to is setting the calibration correctly. Set it to cut off the 4.2 volt output for 1S, hence the 8.4 volt output for 2S. and that's it, you can start using it. If you are not yet a subscriber, you need to subscribe now.

3.7v battery charger circuit with auto cut off

3.7v battery charger circuit diagram

3.7 volt battery charger automatic

Automatic 3.7 volt battery charger circuit

18650 battery charger with auto cutoff

3.7v battery full charge indicator

3.7v battery protection circuit

In this video i'm showing how to make 3.7 volt battery charger circuit with auto cut off on Full Charge.

For that i used TL431 Shunt Regulator, it's actually an adjustable zener.

I used mosfet which remains on by supplying small positive voltage using 1k resistor.

And cut off voltage is set at reference pin1 of TL431 by using resistors from both positive & negative.

When voltage in circuit reaches to threshold point TL431 connects negative voltage from pin2 to pin3 so positive voltage at mosfet gate pin becomes zero and Mosfet turns off.