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Hi,
Could someone answer to the following question?
Are there any issues to supplying voltage to GPIO pins while BCM20736S is powered off ( No power supply to VBAT)?
It's something that is not explicitly mentioned in the datasheet.
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Applying a static voltage to an unpowered chip is always critical and has little to do with the ESD ratings:
- If the input current does not exceed the rating of the protection diode, it is viable. Eventually you have to add a serial resistor to limit this current.
- Especially when applying this scheme to more than a single pin: be aware that this current goes to the supply rail - providing some ill-defined voltage to your chip even when the "normal" power supply is off.
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Are you asking this question in the context of ESD? What is the value of the applied voltage?
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Hi btta,
Actually one of our end customers asking this question and according to them the context is not of ESD.
Applied voltage is 3.3V.
Best,
Wataru Sugimoto
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Is there a reason why a voltage is applied to the pins?
I don't think the 3.3V will damaged the chip, since it can survive those ESD voltages.
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Hi btta,
Sorry my question might have been a bit ambiguous.
Best,
Wataru
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Applying a static voltage to an unpowered chip is always critical and has little to do with the ESD ratings:
- If the input current does not exceed the rating of the protection diode, it is viable. Eventually you have to add a serial resistor to limit this current.
- Especially when applying this scheme to more than a single pin: be aware that this current goes to the supply rail - providing some ill-defined voltage to your chip even when the "normal" power supply is off.