1.03 Classifying Power Supplies

Section 1.0 - Hardware

1.03 Classifying Power Supplies and Characteristics

AC Adapter

AC adapters are used with electrical devices that require power but do not contain internal components to derive the required voltage and power from mains power. The internal circuitry of an external power supply is very similar to the design that would be used for a built-in or internal supply.



Advanced Technology eXtended is a motherboard form factor specification developed by Intel in 1995 to improve on previous de facto standards like the AT form factor. It was the first big change in computer case, motherboard, and power supply design in many years, improving standardization and interchangeability of parts.




Is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.


Is the potential difference between two points or the difference in electric potential energy per unit charge between two points. Voltage can be caused by static electric fields, by electric current through a magnetic field, by time-varying magnetic fields, or a combination of all three.


The term wattage is used to mean electric power in watts. Electric power is the rate at which electric energy is transferred by an electric circuit.


Is the amount of electric charge it can store. The more electrolyte and electrode material there is in the cell the greater the capacity of the cell. A small cell has less capacity than a larger cell with the same chemistry, and they develop the same open-circuit voltage.

Voltage selector switch

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Pin 20

The 20 Pin below is a ATX power supply connector it supplies many different voltages (+3.3V, +5, +12, -12, -5) as well as a number of ground wires and a couple signal wires.


Pin 24

It is the same as Pin 20 but it has 24 pins they added an additional (+3.3V, +5V, +12V) and ground was also added. The 24 pin is mostly used for PCI-e boards. The 4 extra pins simply provide more power to the motherboard.



Video: http://www.youtube.com/watch?v=1pBAcFMAODQ