This little ESP01 based board combines a USB2TTL converter which is enabled only when USB is connected to reduce power consumption, a Li-Ion charger with battery protection and a 3V3 LDO.. When connected to USB power, battery is being charged while ESP01 receives power from USB in a UPS function. Originally designed to allow controlling a 5V addressable led strip, this little module can be used as a programmer or UPS/PSU for ESP boards if not directly connected to an ESP01.

In a pcb a little longer than your typical TP4056 charger module at 40x18mm combines a battery charger & protection ( 1S/500mA Li-Ion charger), a CH340C USB2TTL converter with auto-power-off when external power is missing to reduce idle power consumption in battery mode & a 3V3/800mA LDO powered via a power path allowing constant 3V3 presence at the output in case external source has failed or is missing.

USB2TTL

CHARGER

UPS