The voltage offset due to these currents, however, are separate from the input offset voltage parameter and is related to the impedance of the signal source and of the feedback and input impedance networks such as the two resistors used in the basic inverting and non-inverting amplifier configurations. Input bias current and input offset current also affect the net offset voltage seen for a given amplifier. Chopper amplifiers actively measure and compensate for the input offset voltage, and may be used when very low offset voltages are required.

However, the input offset voltage value may drift with temperature or age. This can be reduced to several microvolts if nulled using the IC's offset null pins or using higher-quality or laser-trimmed devices. Typical values for are around 1 to 10mV for cheap commercial-grade op-amp integrated circuits (IC). This causes the output to be zero at a non-zero value of differential input, called the input offset voltage. However, due to manufacturing process, the differential input transistors of real op-amps may not be exactly matched.

both inputs are at the same voltage with respect to ground), the output should be zero. Īn ideal op-amp amplifies the differential input if this input is 0 volts (i.e. The input offset voltage ( ) is a parameter defining the differential DC voltage required between the inputs of an amplifier, especially an operational amplifier (op-amp), to make the output zero (for voltage amplifiers, 0 volts with respect to ground or between differential outputs, depending on the output type).

Op amp offset