BQ25895: I2C issue

Chan Josh

Prodigy 60 points

Part Number: BQ25895
Other Parts Discussed in Thread: BQ25892

I would like to ask about I2C in BQ25895 ,

As attached file , I can communication with BQ25892 by I2C ,

I can read REG0B (charge STAT) , REG11 (Vbus voltage)

but i can't read Vbat (reg 0E) and Vsys (reg 0F)

there's always feedback 0xFF

Please help

thanksBQ25895-Reg_i2C_test200925.pdf

over 4 years ago

0 ezhao over 4 years ago

TI__Genius 10240 points

Josh,

Please check BQ2589x FAQ https://e2e.ti.com/support/power-management/f/196/t/874557 and find out whether the ADC case is applied. Please disconnect any loading and check the battery voltage near the IC. Is the measurement done on a EVM?

0 Chan Josh over 4 years ago in reply to ezhao

Prodigy 60 points

Hi Eric

It's measurement on my PCBA

when I check the Vbat and Vsys ,there's no any load.

//-------------------------------

SCL: 2.2K pull up to 3.3V

SDA: 2.2K pull up to 3.3V

INT: 10K pull up to 3.3V

STAT: 10K pull up to Vsys

/CE: 10K pull low to GND

Ilim: 270 ohm to GND

TS: REGN------10K ohm-------TS-------10K ohm----GND

DSEL: float

Vbus: 1uF

PMID: 20 uF

Vbat: 10uF

SW: 2.2uH

BTST: 47nF

REGN:4.7uF

0 Chan Josh over 4 years ago in reply to Chan Josh

Prodigy 60 points

Test:

Bat: 4.1V

REGN: 2mV

VBTST: 3.77V

VPMID: 3.68V

Vstat: 3.73V

0 Ning T over 4 years ago in reply to Chan Josh

TI__Guru 57541 points

Hi,

Are you able to read REG10 (VTS), REG11 (VVBUS) and REG12 (IBAT)? Could you please provide all the BQ25895 register values for your test?

Thanks,

Ning.

0 Chan Josh over 4 years ago in reply to Ning T

Prodigy 60 points

Hi Ning

REG10

REG11

REG12

all return 0x00

BQ25895-Reg_test_0930.pdf

0 Chan Josh over 4 years ago in reply to ezhao

Prodigy 60 points

hi Eric

thanks for help , i got the answer.

0 Chan Josh over 4 years ago in reply to Ning T

Prodigy 60 points

Hi Ning

I got the answer, thanks for help

0 Ning T over 4 years ago in reply to Chan Josh

TI__Guru 57541 points

Hi,

It's great that your question is answered.

Thanks,

Ning.

Power management

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BQ25895: I2C issue