fix: route battery output through VIN/5V instead of 3V3

[vtolvr]

the original wiring table connected the TP4056 OUT+ directly to the ESP32 3V3 pin, which bypasses the onboard LDO regulator and exposes the MCU to up to 4.2V from a fully charged LiPo. the ESP32 power rail maxes out at 3.6V so this will damage the chip over time. changed the connection to VIN (labeled VIN or 5V depending on your board) so the AMS1117-3.3 regulator actually does its job. also added a warning about disconnecting the battery before plugging in USB to avoid backfeeding voltage through the TP4056.

[sergiolo428]

Using the LDO will increase the heat right? Isn't it better to use a 3.3v buck? Not sure which one fits better with the 3D case.

[vtolvr]

Using the LDO will increase the heat right? Isn't it better to use a 3.3v buck? Not sure which one fits better with the 3D case.

Nope, your generating less heat then using the USB-C connector for powering it, using USB-C you would give the LDO input 5v, then it needs to kill off 2.7v (times whatever mA your running) as heat, when using a 3.7v lipo your generating WAY less heat, because theres only 0.4v times mA needed to get to 3.3v, and im guessing that LDO isnt getting any hot under normal USB-C? So it wont generate any heat at all using 3.7v

Obviously account for that 3.7v is nominal, a full charge is 4.2v but still way less and wont generate any heat.

Its a super simple change, just move the battery positive from the 3V3 pin to the VIN/5V pin. If you still use 3v3 you risk permanetaly damaging your ESP32 in the long run, as its only 3.3v tolerant