Question

The diodes ${\mathrm{D}}_1$ and ${\mathrm{D}}_2$ used in the comparator circuit usually refer to ______?

Answer 1

Explanation:

1. A comparator is a circuit that compares a signal voltage on one of an operational amplifier's inputs to a known reference voltage on the other input.
2. The diodes ${\mathrm{D}}_1$ and ${\mathrm{D}}_2$ given in the circuit diagram below are clamp diodes. These diodes are used to protect the operational amplifier from damage due to an increase in the input voltage.

Clamp diodes:

1. Clamp diodes could be utilized as a level shifter or perhaps to protect equipment from transitory voltages or fluctuations.
2. A clamp diode consists of a diode that conducts electric current in only one direction and prevents the signal from exceeding the reference value and a capacitor that provides a DC offset from the stored charge.
3. These diodes are called clamp diodes as they clamp the differential input voltages to either $0.7\mathrm{V}\mathrm{or}-0.7\mathrm{V}$.

Therefore, the diodes ${\mathrm{D}}_1$ and ${\mathrm{D}}_2$ used in the comparator circuit are usually referred to as clamp diodes.