
A half wave rectifier is one in which rectification is done for only one half cycle of input AC.
Working:
(i) During the positive half cycle of input AC, A is +ve and B is-ve hence diode is forward biased, it conducts current therefore a current flows through the load resistance, there will be voltage across the load resistance.
(ii) During negative half cycle, A is -ve and B is +ve hence diode becomes reverse biased, it will not conduct current, no current flows through the load resistance and there is no voltage across the load resistance. Thus half cycle of input AC is blocked by the diode. This process is called as half wave rectification. Output is DC but not steady.