Hello I build the following circuit following the example given in the datasheet and tried to test it. For unknown reasons it isn’t charging the battery. To the contrary it discharges the battery, with nothing connected to SYS.
To test this circuit it was solder on an experimental board. K5 was replaced with a 10k resistor. Vusb is provided by a lab power supply, set on 5V. For the battery a 2000mAh LiPo is used, with a voltage of 3,9V.
The circuit shows following behavior:
Without battery:
PG_N, Stat: blinking simulate. 800ms high 500ms low
Vbat: ripples 4,2V-3,8V rise 50ms fall 850ms
Vsys: same as Vbat
With battery
STAT: high
PG_N: short dim flashes. 2400ms between flashes
Vbat = battery voltage
Vsys = battery voltage
Am I missing something? Any input would be helpful.
Thank you