Output swing - clipping

Document created by analog-archivist Employee on Feb 23, 2016
Version 1Show Document
  • View in full screen mode

If I configure the AD8331 with a 1.5V common mode voltage instead off the 2.5V
internal voltage I find that the output clips at a peak of 1.0V but with the
2.5V common mode voltage the signal limits at 4.5V as expected.

Could you tell me if this is to be expected and if so why?


The output signal range for www.analog.com/AD8331 datasheet is specified to
4.5Vpp and Vcm+/-1.125V when Vcm is floating.

These parameters are all meant to describe the physical swing limitations of
the AD8331 output stage, which is capable of going to within 1.375V of ground
and the supply. For 5V supply and Vcm=2.5V the output clips below 1.375V and
above 3.625V.

So, when the Vcm is moved down to 1.5V, the outputs only have 0.125V left to
move before hitting the negative rail.