Input offset voltage

Thread Starter

hp1729

Joined Nov 23, 2015
2,304
Let's say we have a non-inverting op amp circuit with a gain of 100 and an input offset voltage of 5 mV. A ground at the input would result in an output of 5 mV x 100 or 500 mV. Is that right?
An input pulse 1 mV high would still result in an increase at the output of 100 mV, right?
 

#12

Joined Nov 30, 2010
18,222
Now, try it as a comparator running with the gain at open loop.
Set the input offset voltage at + 5 mv for the first test and - 5 mv for the second test.

Then try some scenarios for different input bias current, input bias current offset, input resistors, different noise levels, and different frequencies.
 

crutschow

Joined Mar 14, 2008
27,243
Depending on the polarity of the offset the output could be +500mV or -500mV.
............
Just to be clear to the OP, the offset polarity and magnitude for a particular op amp device is generally random with a voltage limit as given in the data sheet.
 

Thread Starter

hp1729

Joined Nov 23, 2015
2,304
Now, try it as a comparator running with the gain at open loop.
Set the input offset voltage at + 5 mv for the first test and - 5 mv for the second test.

Then try some scenarios for different input bias current, input bias current offset, input resistors, different noise levels, and different frequencies.
True. I can see your point on a voltage comparator.
 
Top