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SN54AC244: Determining Pullup and Pulldown Resistors for OE input

Matty13763
Intellectual 410 points
Part Number: SN54AC244

Hi,

I have the need to add a pullup on OE for one mode on my board design and to add a pulldown on the OE on another mode of my design such that one mode the driver won't be active and in the other mode the driver will be active.

I am going to do this by depopulating one of these resistors.

My question is how do I determine the value for these resistors? I see the leakage current is 1uA. Do I just choose a resistor that won't change the Vih and Vil level on the OE input?

In other words, for the pulldown, if I use a 1K pulldown, I would only see a 1K * 1uA = .001V at the input pin which is well within the Vil specification to ensure it remains low.

And fof the pullup, if I use a 1K pullup, I would see a drop of 1uA * 1K = .001V, 3.3 -.001 = 3.299V at the input pin which is well within the Vih specification to ensure it remains high.

Is that it?

Thanks,

Matty