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If an ESD test is performed on the device, even if the device is not damaged, the LD pin of the BQ76942 will still see a rising voltage, and this will trigger WAKE up. If you want the part to SHUTDOWN again if an ESD WAKE up event occurs, you can program the Auto Shutdown feature in OTP
The description of Auto Shutdown from the TRM is as follows: As a countermeasure to avoid an unintentional wake from SHUTDOWN mode when putting the BQ76942 device into long-term storage, the device can be configured to automatically reenter SHUTDOWN mode afterPower:Shutdown:AutoShutdown Timeminutes if the device boots from SHUTDOWN mode without any valid communications occurring or any charge or discharge current detected.
When the device abnormally wakes up from SHUTDOWN, the FETs will turn on, but they will turn off again, and the part will re-enter SHUTDOWN if the voltage on the PACK and LD pin remain LOW, as you have observed.
Here is a passage from section 13.4.1.8 Power:Shutdown:Auto Shutdown Timeof the technical reference manual that may help to explain this situation:
As a countermeasure to inadvertent wake from SHUTDOWN, the device can be configured to automatically enter SHUTDOWN again after a number of minutes defined by this parameter. If communications occur after the first second, or if charge current is detected, or if discharge current above the SLEEP current threshold is detected after one minute, automatic shutdown is cancelled. If none of those events occur, after this number of minutes, the FETs will be turned off for up to five seconds. During that 5 seconds, if the PACK and LD pin voltages fall, the device will enter shutdown. If the voltage on those pins remain above their respective thresholds, auto-shutdown is cancelled based on a conclusion that a charger is present.
To ensure that the device has re-entered SHUTDOWN, you can check the voltage on the REG18 pin. It should be 0 V when the device is in SHUTDOWN mode, and 1.8 V otherwise. I hope this helps!
