Motivation:
to be able to connect to wired audio devices through bluetooth

Description:
Uses a bluetooth to dc jack module, powered through micro usb

I have a 18650 li ion battery connected to a bms, then connected to a tp4056 li ion battery charger module, for powering the bluetooth module.

the battery through bms is connected to the input pads in the bluetooth module

there is a switch to control the battery voltage output

the whole setup is connected through a zero pcb

we can directly power the bluetooth module directly through micro usb or through the battery.