SMPS:
Switch mode power supply.
Switching regulator to convert electric power supply.

Switching regulator:
Switch a series device on and off.
We use capacitor, transistor, inductor and load.
Switch sets how much charge is transferred to load.

Linear Regulator:
Used to maintain steady voltage.

Why we go for SMPS?
Linear power supplies are very bulky,
We need to handle it with less space so we go for SMPS.

History of SMPS:
1980 HP 8662A 10KHZ-1.28GHZ signal generator went with SMPS.

Types of SMPS:
AT SMPS.
ATX SMPS.
BTX SMPS.

AT SMPS:
Advance technology.
12 pin power connector.
Used in Pentium 1, Pentium MMX, Pentium 2, Pentium 3 CPU.

ATX SMPS:
Advance technology extended.
20 pin power connector.
Used in Pentium 3, Pentium 4, AMD CPU's.

BTX SMPS:
Balanced technology extended.
24 pin power connector.
15 pin SATA power connector.
Used in Dual core, Core2 duo, Quad core, i3, i5, i7 and latest CPU's.

SATA:
Serial advanced technology attachment.
Connects hard drives, optical drives.

SMPS topologies:
Non isolated.
Isolated.

Topologies:
Arrangement.

Non isolated:
Input voltage is assumed to be greater than zero.
If it is negative negate output voltage.

Isolated:
Output of higher or lower voltage than input.

Working of SMPS:
Input rectifier and filter.
Chopper.
Output transformer.
Output rectifier and filter.
Feedback circuit.

Input rectifier and filter:
Rectifier converts AC to DC.

Chopper:
Conversion of fixed DC into variable DC output.
 
Output transformer:
Set down the frequencies of DC.

Output rectifier and filter:

Chopper controller:
If obtained output is less than required frequency than chopper will increase frequency and vice versa.

Advantages:
Small size.
Low noise.
High efficiency.

Disadvantages:
High complexity.
Damages sensitive instruments.
High frequency noise.

Applications:
Machine tool industries.
Security systems.
Computer.
Mobile phone chargers.