POWER SUPPLY for ATX COMPUTERS
This is a conceptual circuit diagram of the power train of a typical ATX computer power supply unit. This schematic does not show the control circuitry, that's why you see all MOSFET gates and transistor bases are open. For clarity, the parts responsible for miscellaneous auxiliary functions, such as current limit, fan control, and OV protection, which are not essential for learning the basic concepts of the power conversion, are not shown as well. For a complete schematic, see for example this annotated diagram of an ATX power supply. Note that unlike generators that convert energy stored in various fuels into electricity, PSUs convert electric energy from one form to another. The AC input receptacle in a PC is an IEC 320 type or equivalent. The fuse "F" is followed by an EMI filter. The filter is normally consists of a combination of differential mode and common mode chokes and capacitors. Its main purpose is to reduce the conducted radio frequency noise emitted from t...