BQ40Z60: The SMBus communication stops

Robert Ploeg

Part Number: BQ40Z60
Other Parts Discussed in Thread: BQSTUDIO

Hi,

I've ran into a strange issue, the communication on the SMBus stops.

Situation:

The battery is part of a system when plugged into mains, the PSU charges the battery and power the system. When unplugged, the battery takes over. Now mains was plugged in, battery was charging to full and after a while there was no communication with the battery anymore. Using BqStudio showed no battery attached. Unplugging mains, the battery delivered power to the system but still no communication.

I had to unplug the battery and plug back in to start communication again. I've discharged the battery a bit and plugged in mains with BqStudio logging. Same situation occured, battery fully carged, and after a while no communication anymore. The LOG file shows a sudden stop of loggin data. I can't figure out what has caused the communication to stop.ncr_p200_5.log

over 1 year ago

0 Wyatt Keller over 1 year ago

TI__Guru** 102355 points

Hello Robert,

The communication is one of our highest priority interrupts, and the gauge should always ACK it's address. Do you have any logic analyzer captures of the communication?

If the TS pins are pulsing and the gauge ACKs it's address, the gauge is active. If the TS pins are not pulsing (at 250ms intervals) then the gauge is in shutdown mode.

Sincerely,

Wyatt Keller

0 Robert Ploeg over 1 year ago in reply to Wyatt Keller

Prodigy 240 points

Hi Wyatt,

Thanks for coming back to me so fast.

Managed to get the same situation yesterday, logged with BqStudio. Battery charged to full and after a while it stops communicating where BqStudio is still logging but no data.

Left the system in standby mode, without power supply, over night, using 83mA. This morning still no communication on with BqStudio. Disconnected BqStudio and measuered on the SMB connector on the board with a scope: SCL high, SDA low. No pulsing.

Connected BqStudio again and the communication started. Readout the battery discharged to 90% in the standby mode over night.

Best regards,

Rob

0 Robert Ploeg over 1 year ago in reply to Robert Ploeg

Prodigy 240 points

Sorr, 1 hickup. On the last logging from yesterday, the communication with BqStudio stopped before the battery was fully charged, i.e. stopped during charging.

0 Shirish over 1 year ago in reply to Robert Ploeg

TI__Guru 57747 points

Hello Robert,

The log file will indicate that there is an error. In the log file that you attached, it has "ERROR : Please check C:\Users\Martyn\Desktop\Battey logs\ncr_p200_5.log.err"

Can you share the corresponding .err file?