I've got a few HTC Desire A8183's in which I would like to power directly off the wall socket.
I've got a 12volt 1amp transformer which I've put through a voltage regulator to bring that down to the required 3.7volts as stated on the back of the phone. WHen I connect the +3.7 to pin 4 of the phone and ground to pin 1 it doesn't boot.
I know there must be something I need to do with the other two pins. Some people say one is for the temperature of the battery and the other is a batter status indicator or something like that which needs a resistor.
I've tried a few different approaches so far. I've linked 1,2,3 to ground and supplied positive 3.7volts to pin4. This resulted in a orange & green flashing light which means it has detected the battery is over heating. I then tried putting a resistor on pin3 to ground of 82KOhms but that didn't help.
Here is some advice which I've already tried; http://www.instructables.com/id/How-to-use-phone-without-battery/?ALLSTEPS
How can I run this phone directly off power? I still have a working battery which I can use for testing the voltage supplied.
Here are the read outs;
Phone 3&4 = 1M1 2&4 = 1M3 Battery 1&2 = 4K7 1&3 = 690K 2&3 = 20.3 @200M 3&2 = 1.1 @200M Battery Pin 1 & 2 = 0V Pin 1 & 3 = 0V Pin 1 & 4 = 3.5V Pin 2 & 3 = 0V Pin 3 & 2 = 0V