1. LINEAR
 1) Large size & Heavy
weight
 2) Transformer is Bulky
 3) Low Noise * EMI
 4) Regulation is 0.1 %
 5) High Operating Cost
 6) Bulky filter Capacitor
SMPS
 1) Small size & Light
Weight
 2) High EMI
 3) Small Transformer
 4) Medium Filter Cpacitor
 5) High Noise
 6) Regulation is 0.3 %
 7) Low Operating Cost

2.  It is Placed after surge filter & consist of
following components
 1) A combination of 4 diodes
 This section is used to convert 230VAC to 300
VDC

3.  1) The electrolytic capacitor of higher voltage
capacity
 C1=330µ f/ 400v, C2=330µ f/ 400v &
 C3=100µ f/ 400v

4.  The Transistors are fixed on the heat sink and
hence easy to identify
 There is another pair of driver transistor
(small size) which are used to drive switching
transistor
 The driver transistor & switching transistor
are coupled together through a small
transformer
called Driver Transformer

5.  A bigger Transformer & is driven from the
collector of the switching transistor

6.  It consists of two groups of diodes

7.  It consists of inductors & capacitors

8.  IC TL 494,It is used to generate the pulses of
different width.It requires some esternal
components like resistors,capacitors and
seramic capacitors for generation of pulses

9.  The switching transistor cannot be driven
directly from PWM IC because o/p of PWM IC
is very less .Therefore ,we need driver circuit
between the switching transistor & PWM IC .
 The coupling of power transistor & driver
transistor is done through the driver
transformer.

10.  The switching transistor cannot be driven
directly from PWM IC because o/p of PWM IC
is very less .Therefore ,we need driver circuit
between the switching transistor & PWM IC .
 The coupling of power transistor & driver
transistor is done through the driver
transformer.