P82B96: I2C pin backdrive

Jejomar Ildefonso

Part Number: P82B96

Hi Team,

Our customer would like to know if the P82B96 would be damaged by a possible 3.3V backdrive if its Sx and Sy pins are held high (pulled to 3.3V) while removing Vcc (5V) from it.

The datasheet stated that the P82B96 does not hold these pins low even when Vcc is low to ensure I2C communication between other devices. What could be the possible effect of this scenario to the P82B96?

Thanks in advance.

Regards,

Jejomar

over 6 years ago

0 BOBBY over 6 years ago

TI__Guru* 78091 points

Hey Jejomar,

I found this e2e post which is similar to what you are asking:

Based on this, you shouldn't see any worry but I don't believe the person who answered the post checked this for sure on the bench. I can make some time tomorrow and see if I am able to back bias the device by putting Vcc to GND and making SY/SX pull up to 3.3V.

-Bobby

0 Jejomar Ildefonso over 6 years ago in reply to BOBBY

TI__Genius 9650 points

Hello Bobby,

Thanks for giving some time to look into this. We'll be waiting for the results of the set-up.

Regards,

Jejomar

0 BOBBY over 6 years ago in reply to Jejomar Ildefonso

TI__Guru* 78091 points

Hey Jejomar,

I checked to see if I saw any backbiasing from Vcc to Sx/Sy and Sx/Sy to Vcc but I didn't see any. The only back biasing I saw came from GND->Sx/Sy and GND->Vcc.

-Bobby

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P82B96: I2C pin backdrive