Input Impedance of AnalogX and Voltage Divider

Guzel Sans · Post by **Guzel Sans** » Sat Sep 23, 2017 9:43 pm

The specification page of AnalogX displays the input impedance of the device to be 10 Megaohms (Link page: https://wiki.autosportlabs.com/AnalogX. Whereas AnalogX takes an input of 5 V.

Let's say I am designing a voltage divider with two resistors of 40 kiloohms and 20 kiloohms.
Now for the loading condition of 10 Mohm, I am still getting the output voltage 16.644. I am using this loading calculator http://www.voltagedividercalculator.com ... r-dc-load/ putting 10 M ohm as the loaded resistors. I do know that raising the resistance values can impact in better output, but this will also reduce current to zero.

In the present scenario, I am getting 0.0000016 A, for higher value resistors I am hoping it to further scale down? So what will be the optimal solution for my case?

Post by **brentp** » Thu Sep 28, 2017 6:23 pm

Hi,

Because of the buffered inputs and that the input impedance is so high, you can effectively ignore any loading on the circuit. You should be able to use a simple voltage divider calculator.

Hope this helps!