BQ24168 I2C PROBLEM

WhiteHorse

Other Parts Discussed in Thread: BQ24168

Support,

We have a customer usingt the BQ24168 and is having trouble with the I2C interface.

The symptom is read errors when the battery is charging. The errors occur at any data rate between standard mode (100kbps) and fast mode (400kbps). The errors increase as charge current increases and decrease as charge current decreases and when the battery is not charging there are no errors. What would cause these errors.

Thanks for your help.

Regards,

John Wiemeyer

over 10 years ago

0 Jeffery Pfarr over 10 years ago

TI__Genius 14317 points

Hi John,

Are the pullups on SCL and SDA to the logic supply voltage? It sounds like system noise on the logic supply may increase with charge level which could effect SDA/SDL timing. Can they provide a schematic and any scope shots of the I2C read cycle? They could test using the EVM to see if they see the problem.

I'll ask the BQ Apps. folks for their input as well.

0 Jeffery Pfarr over 10 years ago in reply to Jeffery Pfarr

TI__Genius 14317 points

John,

I checked with the Apps. folks for this device and here is their response:

"There are no known issues with the I2C (this device). I suspect that you are correct about noise on the line."

0 WhiteHorse over 10 years ago in reply to Jeffery Pfarr

Genius 4430 points

Hi Jeff,

Thanks for your reply. I'll gather from the customer the details you reuqested and get back with you.

Regards,

John Wiemeyer

Power management

Power management forum

BQ24168 I2C PROBLEM