What is SMPS & it's Types?

We are going to study is the most important part of Computer Hardware ie. SMPS - Switched Mode Power Supply. It's main task is to provide Power supply to all the components of the company.

We will cover everything about SMPS , it's working, function and all others.

How SMPS Works ? or What is SMPS working ?

- SMPS converts AC to DC voltage with rectifier. All types of Alternating current is managed by SMPS to convert it in Direct current for further supply of Power.
- The unregulated DC voltage is sent to the filter.
- Inverter convert DC to AC with help of power oscillator.
- Output transformer inverts AC voltage up to down to the required output level.
- Output rectifier and filter: AC output from transformer is rectified.
- For lower voltage uses silicon/schottky diodes used and smoothing the rectified output by using filter.

Now we'll see different types of SMPS. Following are the two types of SMPS :

- At (Advanced Technology)

- Atx/Nlx (Advanced Technology eXtended / New Low Profile eXtended)

AT SMPS :

- Front side power connector to SMPS
- AT style SMPS provides DC output on two 6 pin-connectors (carries DC power to motherboard) and two 4-pin connectors
- Power good flag is setup output voltage stable

ATX/NLX SMPS :

- Doesn't connect directly to power button
- It uses five DC voltage, 20 pin connector.
• PS-ON : When it is low SMPS is ON or else OFF
• 5VSB : supplies power supply to circuits
• PW-OK : power good signal
- Front side power connector to SMPS
- AT style SMPS provides DC on two 6-pin connectors (carries DC power to motherboard) and two 4-pin connectors.

We can check the voltage measurement of the SMPS's using Digital Multimeter.

Now we will see that which are the different Computer SMPS connectors available :

- ATX 20+4 Pin (main power which connects to motherboard
- Molex 3 (this are not much used now-a-days)
- Dell P6 (this are used to provide power directly to the PC)
- SATA power 3 (Serial Advance Technology attachments - two connectors are there, one of them are connected at Harddisks, & DVD ROM)
- 6 Pin PCI Express 2 (it supplies power to Graphic card)
- 4 Pin CPU 12V (it provides power supplies to CPU)
- 6 Pin AUX
- 4 Pin FDD

SMPS are generally of 230V, but they are also available in 450V, 550V & 750V. Based on the usage of our CPU, SMPS of different voltages are installed.