Antec SL300S ATX – Connections:

• 1 x 20 Motherboard Connector
• 7 x IDE (molex)
• 1 x Floppy (mini)
• 1 x PS6
• 1 x 4pin PS

There are two main designs for power supplies: a linear power supply and a switching power supply.

• Linear: A linear power supply designs use a transformer to step down the input voltage. Firstly, it rectifies the voltage then turns it into a direct current voltage. Secondly, it filters it again to improve the waveform quality. Also, linear power supplies use linear regulators to maintain a constant voltage at the output. These linear regulators dissipate any extra energy in the form of heat.
• Switching: On the other hand, a switching power supply design is a newer methodology developed to solve many of the problems associated with linear power supply design, including transformer size and voltage regulation. Consequently, in switching power supply designs, the input voltage is no longer reduced; instead, it’s rectified and filtered at the input. Then the voltage goes through a chopper, which converts it into a high-frequency pulse train. Once again, filtering and rectifying occurs before the voltage reaches the output.

How Does a Switching Power Supply Work?

As a matter of fact, for many years, linear AC/DC power supplies have been transforming AC power from the utility grid into DC voltage for running home appliances or lighting. The need for smaller supplies for high-power applications means linear power supplies have become relegated to specific industrial and medical uses, where they are still needed because of their low noise. But switching power supplies have taken over because they are smaller, more efficient, and are capable of handling high power. Figure 1 illustrates the general transformation from alternating current (AC) to direct current (DC) in a switching power supply.