I set the charge current to be 256mA.
Then I measure the charge current to the barrery is 256mA indeed. ( My battery is 13V now. )
However, I find that the input current ( output current of my 12V adapter) is 0.55A.
If I unplug the battery, let the bq25703a circuit to power my system, the input current will be 0.14A.
which mean that charge a (12.6V) 256mA current will consume (12V) 400mA input current.
The sch and pcb are as follows. Some waveforms and thermal images are attached, too.
In my PCB layout. Gate path is highlighted.
Register settings can be referred from here: BQ25703A: No charge current.
