SMPS simple tricks for checking power supply

The most common type o power supply use today internally in PCs is awitch mode power supply  (SMPS). An SMPS consists of high frequency switch, which is actually a transistor internally, with varying frequency ranging from 50 kHz to 1 MHz. this switch is used to control and stabilize the output voltage by switching the load current on and off.

Identifying power supply Function

The power supply has a wide variety of function in your computer: some of the important function are listed below:

    1. -12 V is the power requirement of some the serial ports. however, it is not provided in new systems and rarely used in order system too. this voltage is provided by power supplies only for compatibility with the older hardware.

2. -5 V is the power requirement of floppy controllers in some of the earliest computer this voltage is provided by very limited Numbers of power supplies and that too for compatibility with the older hardware.

3.0 V: is the base voltage of the computer.this voltage is used as a reference against which other voltage are measured.

4. +3.3 is the power requirement of computer memory, most new processor, motherboard and some of the components on motherboard. This voltage is provided only by the new power supplies (in ATX and later from factors ).and is not available in older systems (in baby AT and earlier form factor).

5. +5 V: is the power requirement of computer memory, processor, motherboard and most of the other system components in the earlier computer systems (in baby AT and earlier).this voltage is also used for most of the motherboard components even in the newer systems (in ATX and later).

6. +12 V: is he power requirement of disk drives, fans and other types of cooling devices.

WIRE         VOLTAGE      FUNCTION
       
Black                 0                  Ground 
Blue                 -12                 Serial Data
Brown/Violet    +3.3               Sensor 
Gray                  +5                  Power good supply 
Green                +5                  Power supply on/off
Orange              +3.3               D Ram Refreshing
Purple               +5                  Stored by voltage 
White                -5                   Refreshing Ram 
Yellow              +12                Motor Rotation 
Red                  +5                   Logic circuit 

GREEN wire port and other in the BLACK. Switch ON the supply if the fan in the smps is working the smps is good.

  

.