Tool/software:
Hello TI team,
I’m working with the BQ7697202 and observing unexpected behavior related to SHUTDOWN wake-up via the TS2 pin. According to the BQ76972 Technical Reference Manual, the device should only wake from SHUTDOWN when:
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TS2 is pulled low (below ~1.5 V),
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A voltage is applied to LD, or
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Any VCx pin exceeds ~1.2 V.
However, in my case:
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I am applying a DC 60 V signal to the TS2 pin.
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A TVS diode is used on TS2 to clamp this voltage below 6 V (within absolute max limits).
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Despite this, the device exits SHUTDOWN and powers up — even though TS2 is not pulled low at any point.
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This is a clean DC signal, not a transient — no falling edge is present.
This behavior seems to contradict the documented wake-up methods, and I want to understand:
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Is there any known internal mechanism that could explain this wake-up due to TVS clamp behavior?
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Could leakage or ESD clamp current on TS2 result in false wake-up detection?
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Are there any undocumented limitations or edge cases related to using TS2 with external clamping?
For completeness:
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The BQ7697202 enters SHUTDOWN via the
SHUTDOWN()subcommand. -
There is no thermistor or pull-down on TS2.
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REG18 is left unused.
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TS2 is connected only to a TVS diode referenced to VSS, clamping at ~5.8 V.
I’d appreciate any insight into whether this is expected behavior or a potential risk of backfeeding or ESD leakage during system design.