Hi,
I am using PB96 for I2C communication on 3m cable. I have undershoots ~ -700 mV on SDA and SCL lines. I added BAT54C schottky diodes to protect the P82B96 from exceeding absolute maximum ratings. Undershoots were reduced to ~ -500 mV (still higher than -0,3 V abs max).
My question is if the undershoots may damage the P82B96? I checked also datasheet of P82B96 from NXP and they show clearly that absolute max ratings at TX, RX lines are DC values only, and short spikes on I2C lines do not lead to any problems and do not need to be clamped. Is it also the case for P82B96 TI? - in other words - is it allowable to have short undershoots exceeding absolute maximum values?
Best regards,
Jakub Kwolek