BQ34Z100-G1: Chip enable

Matej Pinter

Part Number: BQ34Z100-G1
Other Parts Discussed in Thread: BQ34Z100, BQ76952

Tool/software:

Hello,

What is the purpose of chip enable pin?

Sometimes I2C communication is corrupted and we would like to reset the BQ34Z100 and reinitialize I2C so that we are sure nothing is holding the i2c lines. Can we reset BQ34Z100 by toggling the chip enable pin?

Thanks for help, best regards, Matej

over 1 year ago

0 Diego over 1 year ago

TI__Mastermind 28985 points

Hi Matej,

Disabling the CE pin will disable the internal LDO.

How is i2c communication corrupted? is the i2c line stuck low?

Regards,

Diego

0 Matej Pinter over 1 year ago in reply to Diego

Prodigy 60 points

So if we toggle this pin it will cause bq to reset?

We don't know exactly, because it only happens on the field in some cases, it could be some external influence, and we also have bq76952 on the same i2c line. And we can't reproduce the error in the lab. So we are looking for a way to recover after error. We can reset bq76952, but we would like to do the same with bq34z100.

+1 Diego over 1 year ago in reply to Matej Pinter

TI__Mastermind 28985 points

Hi,

If you are trying to reset the i2c engine, holding the i2c lines low for 2s should reset the engine.

Toggling the CE pin will affectively power cycle the device.

Regards,

Diego

0 Matej Pinter over 1 year ago in reply to Diego

Prodigy 60 points

Hello,

thank you for advice. Does this toggling I2C lines low for 2s and resetting I2C engine also apply for BQ76952?

Best regards, Matej

0 Diego over 1 year ago in reply to Matej Pinter

TI__Mastermind 28985 points

Hi Matej,

Let me refer to a monitor expert.

Regards,

Diego

0 Alexis_H over 1 year ago in reply to Matej Pinter

TI__Mastermind 18915 points

Hello Matej,

If you toggle the SCL pin low for around 2 seconds, it will also reset the I2C engine for the BQ76952 as well. The specific timings for I2C communication for our device can be found in Section 7.27 Timing Requirements – I2C Interface, 100kHz Mode or in Section 7.28 Timing Requirements – I2C Interface, 400kHz Mode of the BQ76952 Datasheet.

Best Regards,
Alexis

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BQ34Z100-G1: Chip enable