Junction Diode as a full wave rectifier—Full wave rectifier rectifies both halves of a.c. input signal. The circuit diagram of full wave rectifier as show in figure 16.
The a.c. input signal is fed to the primary (p) coil of the transformer. The p-regions of both the diodes D1 and D2 are connected to the two ends of the secondary coil (s). The load resistance R1 across which output voltage is obtained is connected between common point of n regions of diodes and central tapping of the secondary coil.
Working—When positive half cycle of input a.c. signal flows through the primary coil, induced e.m.f. is set up in the secondary coil due to mutual induction. The direction of induced e.m.f. is such that the upper end of the secondary coil becomes positive while the lower end becomes negative. Thus, D1 is forward biased and diode D2 is reverse biased, So the current due to diode D1 flows throught the output voltage which varies in accordance with the input half cycle is obtained accross the load resistance (R1 ). During negative half cycle of input a.c. signal, diode D1 is reverse biased and diode D2 is forward biased. The current due to diode D2 flows through the circuit in a direction shown by arrows (below R1 ). The output voltage is obtained across the load resistance (R1 ).
