Fully differential op amp common mode output voltage THS4500

gwt_3

Fully differential op amp common mode output voltage THS4500 [Copy link]

 

When VOCM=0.9V, the output of this circuit is clipped when VO- and VO+ are below 0.78V. Only when VOCM is above 1.4V will the output be normal. Changing the input FPA-OUT gives the same result. I don't know why. Is it a problem with the THS4501 device or the circuit?

chunyang

Looking at the device manual, the output voltage of a non-rail-to-rail op amp cannot be close to the ground potential and the power supply potential. The solution is either to increase the power supply voltage margin or to switch to a rail-to-rail op amp.