A **half-wave rectifier** is a simple electronic circuit that allows current to flow in only one direction, effectively converting alternating current (AC) into direct current (DC).
In AC, the current alternates direction periodically. A half-wave rectifier uses a **diode** to block either the positive or negative half of the AC signal, allowing only one half (positive or negative) to pass through. This way, it "rectifies" the AC signal, producing a pulsating DC signal.
### How it works:
- During the **positive half-cycle** of the AC signal, the diode conducts, allowing current to flow through the load resistor.
- During the **negative half-cycle**, the diode is reverse-biased and does not conduct, so no current flows.
As a result, the output is a pulsating DC signal that only contains one half of the AC waveform (either the positive or negative half, depending on the orientation of the diode).
### Key Points:
- Simple and inexpensive circuit.
- Only one half of the AC signal is used.
- The output is not a smooth DC; it's a pulsating DC.
This type of rectifier is commonly used in low-power applications where high efficiency and smooth DC output are not critical.