One kind of full-wave rectifier, called the center-tap design, uses a transformer with a center-tapped secondary winding and two diodes, as in the figure below.įull-wave rectifier, center-tapped design.

Such a circuit is called a full-wave rectifier. If we need to rectify AC power to obtain the full use of both half-cycles of the sine wave, a different rectifier circuit configuration must be used. This circuit is perhaps the crudest possible method of pulsing power to a load, but it suffices as a proof-of-concept application. Since the controlling device (the diode, in this case) is either fully conducting or fully nonconducting at any given time, it dissipates little heat energy while controlling load power, making this method of power control very energy-efficient. This principle of “pulsing” power rapidly to a slow-responding load device to control the electrical power sent to it is common in the world of industrial electronics. Instead, its filament merely operates at a lesser temperature than normal, providing less light output. Because the half-wave rectified power pulses far more rapidly than the filament has time to heat up and cool down, the lamp does not blink. In the “Dim” switch position, the incandescent lamp receives approximately one-half the power it would normally receive operating on full-wave AC. Half-wave rectifier application: Two level lamp dimmer. Some two-position lamp dimmer switches apply full AC power to the lamp filament for “full” brightness and then half-wave rectify it for a lesser light output. Half-wave rectification is, however, a very simple way to reduce power to a resistive load. Furthermore, the AC power source only supplies power to the load one half every full cycle, meaning that half of its capacity is unused. The harmonic content of the rectifier’s output waveform is very large and consequently difficult to filter. Half-Wave Rectificationįor most power applications, half-wave rectification is insufficient for the task. It only allows one half of an AC waveform to pass through to the load. The simplest kind of rectifier circuit is the half-wave rectifier. As we have seen, this is exactly what a semiconductor diode does. This involves a device that only allows one-way flow of electric charge. Simply defined, rectification is the conversion of alternating current (AC) to direct current (DC). Now we come to the most popular application of the diode: rectification.

Rectifier diode for battery charger