StateTime and ElapsedTime of log count of BQ40Z50 fuel gauge

Jason Zhou

Other Parts Discussed in Thread: BQ40Z50, BQSTUDIO, EV2400

When using the BQ40Z50 fuel gauge to detect the battery status, the StateTime counted by BQstudio's log is smaller than the ElapsedTime as time goes by. For example, after one hour, the time is 20 seconds less. What is the reason for this? As shown below.

over 1 year ago

0 Wyatt Keller over 1 year ago

TI__Guru** 102465 points

Hello Jason,

The StateTime is read from the gauge and is used for internally tracking for the gauge. It is not critical for this to be extremely accurate. The ElapsedTime is from the EV2400 module and BQStudio and is a more exact time reference.

Sincerely,

Wyatt Keller

0 Jason Zhou over 1 year ago in reply to Wyatt Keller

TI__Prodigy 190 points

Thank you very much for your answer, so is the error size between the two uncertain and who is faster and who is slower? What error range is generally reasonable?

0 Wyatt Keller over 1 year ago in reply to Jason Zhou

TI__Guru** 102465 points

Hello Jason,

We don't have specification data for this, since both time measurements may have some error it may be less error in reality than what the bqStudio log shows.

Sincerely,

Wyatt Keller

0 Jason Zhou over 1 year ago in reply to Wyatt Keller

TI__Prodigy 190 points

Oh, thank you for your answer, I get it, so it doesn't matter who is faster and who is slower, right? This error is normal, the internal timing of the fuel gauge will not be so accurate

+1 Wyatt Keller over 1 year ago in reply to Jason Zhou

TI__Guru** 102465 points

Hello Jason,

Correct, it shouldn't matter in the gauges perspective over long periods of time small errors are not critical.

Sincerely,

Wyatt Keller

0 Jason Zhou over 1 year ago in reply to Wyatt Keller

TI__Prodigy 190 points

I got it, thank you!

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StateTime and ElapsedTime of log count of BQ40Z50 fuel gauge