After unpluggin the USB connector, current is observed leaking from the VBUS pin. The VBUS pin measures at 2.338V. Switching power off and back on clears the condition.
What causes this? Can it be corrected in software?
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After unpluggin the USB connector, current is observed leaking from the VBUS pin. The VBUS pin measures at 2.338V. Switching power off and back on clears the condition.
What causes this? Can it be corrected in software?
Does this occur every time VBUS is removed? Is there any circuit connected between VBUS and VBAT besides the charger. Can you ask a 10k resistor at VBUS?
1) Yes. It happens every time when VBUS removed
2) No. There is no direct circuit between VBUS and VBAT.
3) As you can see the schematic below there is a serial resistor and LED between VBUS and GROUND.
But here indirect circuit between VSYS and VBUS. There is CP2102 powered by VSYS and it has connection to VBUS (see drawing below).
While current leaking happens, the VBUS is 2.4V and the VBUS pin of CP2102 has value 1.52V.
The leaking current does not happen when Rtop is removed.
"The leaking current does not happen when Rtop is removed.": When RTOP is removed, what is the voltage at VBUS pin of CP2102? When RTOP is removed, what is the voltage at VBUS pin of BQ25619? Any other circuit on VBUS at all?
HI, Alex:
If RTOP resister is removed, I understand that VBUS pin of CP2102 is 0 volts. My question is: what is the voltage at TI device BQ25619's VBUS pin without RTOP resistor?
As the workaround for this issue, was implemented power-off (by BATFET_DIS) after the state PW_GOOD goes to FALSE. That makes PowerOff every time after the USB cable unplugged.
Alternative way was to make short pulse of HIZ after PW_GOOD goes to false. But that approach did not fix the issue.
Good to see BQ25619 has no voltage at VBUS when CP2102 resistor is removed.
I took a look at CP2102 datasheet, it says " VBUS Sense Input. This pin should be connected to the VBUS signal of a USB network. A 5 V signal on this pin indicates a USB network connection.", what if you connect VBUS directly to VBUS pin of CP2102?