BQ24195: BQ24195 can not quit boost mode

Hi there,

Do you have any load on PMID? Can you check the SW node and find out whether the converter is still switching? The load on PMID or SW waveform will help to find out the reason of the remaining 5V on PMID. You might also want to read back REG01 to check the value. You can also try to set REG01[5:4] = 01 find out whether the state changes.

Best regards,

Eric

Hi ezhao

Thanks for your reply.

When I set REG01[5:4] = 00B, read back the value of REG01[5:4] is 00B, all resiger values are as follows:

when i set it 01B, the value is 01B. so, it is expected value.

I still check the waveform of SW node:

and PMID pin:

the schematic:

Hi,

The PMID is about 5.1V-5.2V, indicating the OTG boots is still in operation. For debugging purpose, can you pull OTG low to find out whether charger can exit the OTG boost mode? Please also try to let the watch dog timer expired so the register can be reset to the default state to exit the OTG boots mode. Do you have a TI EVM to make a comparison test using bqStudio?

Regards,

Eric

Hi Eric,
Thanks for your suggestions.

"can you pull OTG low to find out whether charger can exit the OTG boost mode?"
<-------------------------yes, when pull OTG low, can exit.
Battery voltage is 4.0v, I test in two methods:
1.Use tweezers to make OTG pin connect to GND, and it exit boost mode immediately, Vpmid = 3.65 v. But when I raise tweezers, back to boost mode again, Vpmid = 5.09 v.
2.Plug in 5v adapter, OTG goes low, Vpmid = 5v. Plug out adapter , and OTG goes high again, but something different ---- sometimes, it back to boost mode again(Vpmid = 5.09v), but,sometimes not(Vpmid = 3.65v).

"Please also try to let the watch dog timer expired so the register can be reset to the default state to exit the OTG boots mode."
<-------------------------I have tested it, when the watch dog timer expired,REG[09] = 1B and the registers are reset, but still can not exit OTG boost mode. I have also tried to set REG[01] = 1B to reset registers to default, The phenomenon is the same as watch dog timer expired.

"Do you have a TI EVM to make a comparison test using bqStudio?"
<-------------------------no, I don't have.

Hope you can get what I mean.
My English is so poor, i have to use google translate again and again, so tired.

hi,
I find the reason and now can exit boost mode.
It is caused by TPS7A7001:
wrong operate : step 1---disable TPS7A7001. 2---set REG01[5:4] = 00B
right operate: step 1 ---set REG01[5:4] = 00B. step 2---disable TPS7A7001.

Hi,

Does this mean that writing REG01[5:4] = 00 was not executed in the case not able to exit OTG?

Regards,

Eric