BQ40Z50: The timer for CTO feature(Fast Charge Timeout Protection)

Intellectual 2060 points

Part Number: BQ40Z50

Hi Team,

My customer would like to verify CTO feature but they want to check this timer during the test. Is there any way to read the current "CTO time"?

over 3 years ago

0 Wyatt Keller over 3 years ago

TI__Guru** 105590 points

Hello Cheer,

There is no way to readout the timer, it is internal. The CTO delay will need to be set and then timer verified when the CTO trips.

Sincerely,

Wyatt Keller

0 HY over 3 years ago in reply to Wyatt Keller

TI__Intellectual 2060 points

Hi Wyatt,

Noted. One more question, how to defined the tolerance of CTO:timer?

0 Wyatt Keller over 3 years ago in reply to HY

TI__Guru** 105590 points

Hello Cheer,

All firmware based protections are up to +1 sec worst case since the check in firmware occurs on 1 second intervals.

Sincerely,

Wyatt Keller

0 HY over 3 years ago in reply to Wyatt Keller

TI__Intellectual 2060 points

Hi Waytt,

But this value in their setting should be 36000(10hours). It seems not to control by FW mechanism. Should it be counted by HFO(High-Frequency Oscillator) or LFO(Low-Frequency Oscillator)?

0 Wyatt Keller over 3 years ago in reply to HY

TI__Guru** 105590 points

Hello Cheer,

This is still controlled by firmware, for longer time periods the error may be slightly higher but I do not have specific details on the range of the delay. Most of the timers used are based on the state time, so it is the same clock which is incremented by firmware.

Sincerely,

Wyatt Keller

Power management

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BQ40Z50: The timer for CTO feature(Fast Charge Timeout Protection)