Rectification using a diode

The diode can be used as a simple rectifier because of the difference in its forward and reverse bias properties.
The effect of a single diode on an a.c. voltage is shown in Figure 1(a) and 1(b); this is known as half-wave rectification. The addition of a capacitor will produce a smoothing effect on the output, as shown in Figure 1(c).

Bridge rectifier circuit

Full-wave rectification may be obtained using the bridge rectifier circuit. This is basically four diodes connected in a square (Figure 2) and once again the smoothing effect of a capacitor is shown.



The action of the bridge rectifier can be explained as follows. If point A is positive diode 2 conducts, making D positive. If point B is positive diode 4 conducts, still keeping D positive.