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ADG708 Internal Pulldowns

Hi all,

I have to use an old PCB for a new project and in this PCB many ADG708 are used as demultiplexers, i.e. the D-Pin is used as an input and the S1 to S8 as outputs. My first problem was that the outputs Sx were LOW when not selected. I need a HIGH when the channels are not selected.

Therefore I connected pullups to all of the Sx pins. Unfortunately this did not solve my problem. Now the pins are set to 0.5V, my power supply is 3.3V. At the pullups there is a voltage of 2.7V.

So my question is if there are internal pulldowns at the Sx pins. That would at least match my observations. I used 20 kOhms as pullup value. In the datasheet I did not found any information but perhaps I just missed the correct line in a table.

So thank you very much for helping!

Kind regards