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LAB#2b: HALF-WAVE RECTIFIER CIRCUIT WITHOUT AND WITH FILTER
Objectives:
1. To construct a half-wave rectifier circuit and analyze its output.
2. To analyze the rectifier output using a capacitor in shunt as a filter.
Overview:
The process of converting an alternating current into direct current is known as rectification.
The unidirectional conduction property of semiconductor diodes (junction diodes) is used for
rectification. Rectifiers are of two types: (a) Half wave rectifier and (b) Full wave rectifier. In a half-
wave rectifier circuit (Fig. 1), during the positive half-cycle of the input, the diode is forward biased
and conducts. Current flows through the load and a voltage is developed across it. During the negative
half-cycle, it is reverse bias and does not conduct. Therefore, in the negative half cycle of the supply,
no current flows in the load resistor as no voltage appears across it. Thus the dc voltage across the load
is sinusoidal for the first half cycle only and a pure a.c. input signal is converted into a unidirectional
pulsating output signal.
Fig.1: Half-wave rectifier circuit
Since the diode conducts only in one half-cycle (0-π), it can be verified that the d.c. component in the
output is Vmax/π, where Vmax is the peak value of the voltage. Thus,
