What is the primary use of a Zener diode?

The primary use of a Zener diode is to stabilize voltage levels in circuits. Zener diodes are designed to operate in the reverse breakdown region, allowing them to maintain a constant voltage across their terminals even when the current flowing through them changes. This characteristic makes them extremely valuable for voltage regulation applications.

In practice, a Zener diode can be used in a circuit to provide a stable reference voltage, which is crucial in power supply circuits where fluctuations in input voltage could otherwise affect the performance of sensitive electronic components. By providing this stability, Zener diodes help to protect circuits from overvoltage conditions and ensure that regulated voltage levels are maintained for proper operation.

This function distinguishes Zener diodes from regular diodes, which typically do not have the ability to stabilize voltage levels in the same way. Other options mentioned, such as rectifying AC signals or amplifying signals, describe functions associated with standard diodes and transistors, respectively, and switching high power loads typically involves devices designed specifically for that purpose such as power transistors or relays. Thus, the role of the Zener diode is clearly oriented towards voltage stabilization.