74AVC2T244 slow slew power supply

Mike DeVita

Hi,

I am looking at translating a signal from 1.2V to 3.3V using the 74AVC2T244. I need to detect when a 1.2V signal rises above 1V while the Output Enable is held low. If the VCCA supply slew rate is in microseconds for 1.2V, the VCCA signal inputs are already pulled up to a stable 1.2V, and the VCCB supply is at a stable 3.3V during the duration, what is to be expected at the VCCB signal outputs? They will switch from off to on when the VCCA rail reaches what percent of VCCA (1.2V)?

over 10 years ago

0 Emrys Maier over 10 years ago

TI__Guru* 97046 points

Moving to the voltage translation forum for support.

0 Jennifer Joseph over 10 years ago

TI__Intellectual 2530 points

Hi MikeThe specs you want to look at are VIL, VIH, VOL, VOH.
0.9* Vcca for 1.2V Vcca according to the datasheet. Thanks

0 Mike DeVita over 10 years ago in reply to Jennifer Joseph

Prodigy 250 points

Hi Clarissa,

Thanks for your response. Are you saying that as soon as VCCA comes up to 0.9*VCCA (1.08V for 1.2V VCCA) the inputs become valid? In my description I have the A and B inputs pulled high to a different 1.2V supply that is already up prior to the 1.2V for the VCCA supply.

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74AVC2T244 slow slew power supply