UCC27517: IN pin input while VDD is off

Kazuki Itoh

Part Number: UCC27517

Hello team,

Could you please let me know if IN pins accept 3.3V signal while VDD is off?

The datasheet mentions that Input Pin Absolute Maximum Voltage Levels Not Restricted by VDD Pin Bias Supply Voltage, but I'd like to make sure this should be OK just in case.

Regards,

Itoh

over 3 years ago

0 Mamadou Diallo over 3 years ago

TI__Genius 13445 points

Itoh-san,

Though the voltage on INx pins is independent of VDD supply levels, the proper sequence for power up/down is recommended to be VDD before applying any voltages on INx pins and for power down INx off, followed by disabling the supply. This is to prevent activating the ESD cells on the input stage of the IC.

Regards,

-Mamadou

0 Kazuki Itoh over 3 years ago in reply to Mamadou Diallo

TI__Genius 9165 points

Hello Mamadou,

Thank you for prompt support.

I think this DS description is a little confusing, so I'd appreciate if you clarify this in the next DS update.

Regards,

Itoh

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UCC27517: IN pin input while VDD is off