TP4056 Lipo charger with voltage regulator for OEM issues

Thread Starter


Joined Jun 27, 2023
Hi all,

Im relatively new to PCB design and schematics, A new skill I'm learning at my company is to try to bring some components in-house. We currently have a PCB in place where just voltage regulates 5v from the wall plug and the standard 3.7v from the battery to the OEM but it does not do any smarts in charging the Lipo battery. Because our work involved designing and manufacturing bespoke items it's very hard to buy off-the-shelf items and have them fit or work as needed. This is why I'm busy redesigning and improving on our current devices.

I've been able to combine both a standard TP4056 Circuit with voltage regulation and I've printed the PCB, however, it is not working as intended. When testing the current instead of the intended 300mA with a 4k Ohms RProg, I'm only getting 30mA when I change the 4k RProg to 400 Ohms then I get 300mA (These are not exact figures just simplifying it). Im not sure what I've done wrong or where I've gone wrong.

I've attached my circuit and the PCB design showing top(red) and bottom(blue) layers.

The module will be situated internally, therefore I've removed the normal LEDS that are in the circuit.

Hopefully, someone can help or point me in the right direction. Thank you