What is a key characteristic of a half wave rectifier?

A key characteristic of a half wave rectifier is that it utilizes one diode to allow current to flow in only one direction. This single diode is responsible for blocking the negative portion of the AC waveform, which results in rectifying the input voltage into a pulsating DC output.

This characteristic is fundamental to the operation of a half wave rectifier, as it directly affects how the device converts alternating current (AC) to direct current (DC). The use of a single diode limits the current flow to only one polarity, meaning that during one half of the AC cycle, the current is allowed to pass, and during the other half, it is blocked, effectively reducing the output frequency to half of the input frequency.

In comparison, the use of two diodes would be a characteristic of a full wave rectifier, where current can flow through both directions during different parts of the AC cycle. The claim that it doubles the voltage output compared to the input also misrepresents a half wave rectifier's function, as it typically results in a lower average output voltage due to the absence of the negative half of the AC waveform.