Linux/BQ27741-G1: BQ27741-G1 : After long run i2c slave is not detecting.

naveen kumar79

Part Number: BQ27741-G1

Tool/software: Linux

Hi Team,

we are using BQ27741-G1 IC for reading battery percentage, BQ27741 IC connected in 12c-1 bus with 3.3V and pull-up resistors 4.7K .

we are using 4.4.11 kernel and raspberry pi 3 board. Initially after power ON i2c slave(0x55) detecting properly, after long run (2 days) BQ27741 ic not detecting in i2c bus (conformed with i2cdetect -y 1 command).

after reboot board detecting i2c slave with proper address(0x55), This issue seen first time.

Please any one help me on this.

Regards,

Naveen.

over 7 years ago

0 Phil Yi40 over 7 years ago

TI__Mastermind 38901 points

Hi, Naveen,

Would you please check the voltage on the pin VPWR? if it's lower than 2.45V after 2 days long run, the I2C could not be detected properly; after reboot board, may be without load, the battery voltage relax a bit to above 2.45V, and then it's detectable again.

Thanks!

Phil

0 naveen kumar79 over 7 years ago in reply to Phil Yi40

Prodigy 220 points

Hi Phil,

Thanks for the reply,

Sure i will check when hit this next time , we again started long run , any other method to detect slave without reboot.

please can you help me on this.

Regards,

Naveen.

0 Phil Yi40 over 7 years ago in reply to naveen kumar79

TI__Mastermind 38901 points

Hi, Naveen,

If it's caused by battery over-discharge (UV), you can apply a charge for a while, when VBAT rising up above 2.8V, then I2C will be detected.

Thanks!

Phil

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Linux/BQ27741-G1: BQ27741-G1 : After long run i2c slave is not detecting.