BQ27220: Wrong DEVICE_NUMBER

Gabriel Arnautu

Part Number: BQ27220

Hi,

I have a BQ27220 development board. I have connected it to an Arduino and I am using this library. I know that is not for this IC, but the DEVICE_NUMBER reading is the same. The problem is that it returns me 0x00FF.

The logic analyzer records the I2C traffic as this:

over 6 years ago

0 Gabriel Arnautu over 6 years ago

Intellectual 345 points

It looks like I have to read from 0x40, not from 0x00 and wait 1 second before doing the reading. This is working if I use an Arduino.

I want to actually implement it for ESP32, but the problem is that BQ27220 doesn't respond after the 0x40 request.

0 Onyx Ahiakwo over 6 years ago in reply to Gabriel Arnautu

TI__Guru* 76230 points

Have you looked at the app note below:

thanks

Onyx

0 Gabriel Arnautu over 6 years ago in reply to Onyx Ahiakwo

Intellectual 345 points

Hi, the problem was that my ESP32 had a bad timeout. I increased it and also added a delay between subcommand and register reading and it's working now.

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BQ27220: Wrong DEVICE_NUMBER