AnsweredAssumed Answered

AD5290 can not reach zero (and max) value, if applied as voltage divider ?

Question asked by koebi on Dec 2, 2014
Latest reply on Dec 4, 2014 by musach

In the brochure "Understanding and ApplyingDigital Potentiometers" written by

Chris Hyde and Dave Lunsetter, I found a good overview of different digipots

in different applications published by Analog Devices.


3 wire links from a AD5290 to a microcontroller proto board observe me, that the

AD5290 obvious can not reach absolute zero and also can not reach absolute max.

values if used as three terminal potentiometer (as voltage divider).


My personal selection of AD5290 is based on a must of +-15V (AC/DC) range and 8bit

resolution and avail. in several kOhms ranges.


Is there an other architecture avalilable from AD with virtual absolute connection

of W to A and W to B, when applied as potentiometer to get a FULL range potentiometer?

It is fully clear to me, that a minimal resistor value of some ten ohms is left if used

as rheostat, as potmeter not relevant. 


Any hints?