A rectifier converts alternating current (AC) to direct current (DC) using diodes. There are different types of rectifiers: half wave rectifiers use one half of the AC wave, while center-tapped and bridge rectifiers use the entire AC wave through two or more diodes. Rectifiers are needed to provide DC power for electronic circuits from an AC source. The AC is first stepped down with a transformer, then rectified into pulsating DC using diodes, and filtered into steady DC voltage using capacitors or inductors. Proper selection and use of rectifiers allows conversion of AC household current into the DC power required by many electronics.

1. Rectifiers

2. What is a rectifier?
 The device which converts a
bidirectional AC to pulsating
(Unidirectional) is called as rectifier.
 This rectification is achieved by the
electronic element called
semiconductor diode.
What is a diode?
When a p-type semiconductor is
suitably joint to n-type semiconductor
by special fabrication technique is
known as semiconductor diode or
crystal diode.

3. Need of Rectifier
 Every electronic circuit such as
Amplifier Needs a D.C power source
for its operation.
 To obtain D.C supply voltage,the A.C
supply has to be reduced using
transformer.
 Elements for conversion:
A. Rectifiers i.e Diode
B. Filter i.e Capacitor/inductor

4. Types of Rectifiers
Full WaveHalf
wave
Centre Tap Bridge

5. Half wave Rectifier
Operation:
1.During positive half cycle the diode is forward biased and diode
current flows through it, this current flows through load resistor(RL)
and develops a voltage across it. This is the out put dc voltage
2.During negative half cycle the is reversed biased and diode current
does not flows through it, there is no load current across the resistor
(RL) as a result the out put dc voltage during negative half cycle is
A rectifier in which the positive or negative half of
the AC wave is passed, while the other half is
blocked is called as half wave rectifier.

6. Center-taped full wave rectifier
A center tapped full wave rectifier is a type of rectifier which uses
a center tapped transformer and two diodes to convert the
complete AC signal into DC signal.
Operation:
During positive half cycle A becomes positive and N becomes
negative so Done is in forward and d2 is in reversed biased and
current will only flows from done through RL to secondary winding.
During negative half cycle B becomes positive and A becomes
negative, so d2 is in forward biased and d1 will be ne reversed
biased and no current will flow through Done the current flows
through d2 through RL to secondary winding

7. Full wave bridge Rectifier
 A Full wave rectifier is a circuit arrangement which makes use of
both half cycles of input alternating current (AC) and convert
them to direct current (DC).
OPERATION:
During positive half cycle p is positive and Q is negative diode D1
and D2 are forward biased where as D3 and D4 are reversed
biased the load current and load voltage both are positive.
During negative half cycle Q is positive and p is negative D3 and
D4 are forward biased and D1 and D2 are reversed biased the
load current and load voltage both are negative.
RL
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Q
P

8. CONCLUSION:
Hence by using the different types of
rectifiers i.e half wave, full wave rectifiers
we can convert AC into Dc with the help of
Step down transformer ,rectifiers and filters