Cheap handheld : Fixing the battery charging circuit



 Let's use a TP4056 / TP 5100 on the back of the board (there is enough room if you are careful)

Schematic change: Basically remove the 2 diodes and the 2ohm resistor add tp4056/tp5100


NB:

It's difficult to have the protection working with the TP4056 as the negative battery is connected directly to the PCB ground

The battery is ~ 600 mAH (it's written 1020 mAH but you know how it works), so a sweet charging spot is ~ 300 mA

With the TP5100 that means R=330 mOhm, i dont have that so i took 2x 1 Ohm = 0.5 Ohm instead to get 200 mA, that's a bit low but well.... 

(with the TP4056 that would be 4k, much easier to get)


The board actually consumes about 200mA






That's one problem fixed, i.e. dont stress the battery


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