BQ40Z80: SMB connection error

David Park

Expert 6680 points

Part Number: BQ40Z80
Other Parts Discussed in Thread: BQSTUDIO, EV2400

Hi,

There is communication error between EV2300/2400 and BQ40Z80.

Sometimes connection is ok but sometimes error occurs.

PC and EV2300/2400 connection is ok but EV and BQ connection is error.

Attached picture is SMBC and SMBD.

What do I have to check more?

over 6 years ago

0 Batt over 6 years ago

TI__Mastermind 42535 points

Please use the ev2400. What version does bqstudio say the ev2400 is?

0 David Park over 6 years ago in reply to Batt

TI__Expert 6680 points

Hi Batt,

version is 1.3.86 and customer is using EV2400.
It's same with EVM as well.

Thanks.

0 Batt over 6 years ago in reply to David Park

TI__Mastermind 42535 points

Hi David,

Which rev of the evm did you get? We made some changes from the E1 to rev B. However, none of them had comm issues. Maybe your line needs a stronger pullup.

0 David Park over 6 years ago in reply to Batt

TI__Expert 6680 points

Hi Batt,

I checked it again with Rev.B board through on board EV2400.
After wake switch on, I could contact BQ40Z80.
But after 2~3s, it's disconnected.
When I push the wake button again, I could contact BQ40Z80 again but it's disconnected again.

When I tried it, I didn't connect the load.
Do I have to connect the load?

BQstudio version is 1.3.86 and power supply is 32V for cell simulation.

Thanks.

0 Batt over 6 years ago in reply to David Park

TI__Mastermind 42535 points

Keep the pack side or charger side connected. If it sees a voltage there it will stay up.

Power management

Power management forum

BQ40Z80: SMB connection error