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What are opamps?

Typical Parameters (Input Offset Voltage)

Input Offset Voltage

With an input offset voltage and differential input circuit, ideal opamps and comparators will have an offset voltage of 0V, including error voltage.
When inputting a common-mode (same) voltage to the input pins of an opamp or comparator, with an ideal opamp no output voltage will be output, but in the case where an input offset voltage exists, a voltage will be output based on the input offset voltage.
This input offset voltage, which is the differential voltage required to make the output voltage 0V, becomes the input conversion value.
The benefit of expressing in terms of input conversion is that utilizing input conversion voltage makes it easy to estimate the effects on the output voltage, even with opamps and comparators featuring different amplification rates and circuit configurations.
Offset voltage is normally expressed in units of mV or µV.
Values closer to 0 are more ideal.

Input Offset Voltage Illustration

The offset voltage increases rapidly out of the common-mode input range, and in this region opamps and comparators cannot operate. In addition, if we observe the frequency occurrence of the offset voltage, we will see that the normal distribution will center around 0V.
In other words, it will be stochastically distributed within the defined range.
Normally, since the representation of the standard value is described as an absolute value, both + and - offset voltages exist.

Opamp/Comparator BasicsApplication Notes