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BQ7716: Interaction of BQ771600 and BQ40Z50 during Cell-over-voltage events

Part Number: BQ7716
Other Parts Discussed in Thread: BQ40Z50, BQ7718

Assume the following setup of cell-over-voltage (COV ) for both primary detection (BQ40Z50) and second level (BQ771600 variant)

4.3v    BQ771600 COV detection value (BQ7716x data sheet)
4.25v  BQ40Z50 COV value (set in GG file)
4.1v    BQ40Z50 recovery value (set in GG file)
4.05v  BQ771600 COV recovery hysteresis threshold (BQ7716x data sheet highest value)

3.9v   BQ771600 COV recovery hysteresis threshold (BQ7716x data sheet lowest value)

Assume that as configured, both the BQ40Z50 and BQ771600 can independently blow the chemical fuse.

Assume a transient COV event caused by a less-than-well-behaved charger that drives one cell to 4.31 volts for 0.25 seconds

Assume the cells are nearing full charge (around 4.1volts) and the transient charge voltage pushes one of the cells up to 4.31 volts

Both the BQ40Z50 and BA771600 detect this COV and the BQ40Z50 disables the charge FET

Two timers are started, in this case, 2 seconds for the BQ40Z50 and 1.5 seconds for the BQ771600
After the charge FET is disabled, the cells drift down to 4.1volts (as the transient over-voltage is disconnected)
Assuming BQ40Z50 has reached the 4.1v recovery threshold, in less than 2 seconds, it re-enables the charge FET after 2 seconds

But the 4.1V BQ40Z50 recovery threshold is above the BQ771600 hysteresis threshold, so after 1.5 seconds, the chemical fuse is blown by the BQ771600.

Is my understanding of the BQ771600 operation, in this case, correct? 

The recovery threshold (after the hysteresis values are subtracted) may cause a fuse blow at a relatively low cell voltage (as low as 3.9volts for the BQ771600). 

Thanks