BQ24040: BQ24040DSQ

Hi,

The voltage on ISET is regulated to 1.5V when in constant current phase of charging, will be 0 V when not charging.

If device is not charging, check TS voltage. It may be out of range and disabling charger.

Is this being tested with a battery simulator or eload? These often do not pass the battery detect, look at the waveform on the OUT pin.

Best,

This is tested with battery; Voltage of battery doesn't change;

Vts=0.5V  Viset=0V  Vnchg=3.3V  Vout=3.2V

Is the bq24040 failure?

Please upload the schematic here. May be something else.

Thanks,

Hi,

Schematic looks ok. Are you seeing this issue on multiple units?

Also can you get an image of the waveform on the OUT pin?

Best,

This issue only happened in one unit;

Waveform on the out pin is staight line, voltage equals voltage of battery;

When remove the battery, Waveform on the out pin is triangular wave：

Best Regrads

Hi,

The triangle waveform is expected when battery is disconnected.

IC could be damaged yes.

You could also try eload/ battery simulator to see if issue is the same. OR different battery.

Input is 5V correct?

Thanks,

The same thing happens for other batteries; It is nothing to do with the battery.

5v is correct;

So I think IC was damaged;

I don't understand It can work sometimes.

Best Regards