ABSTRACT
Switching regulators have required the engineer to put a significantly more analytical effort into the design of the input filter. The current pulse, induced by the switching regulator, has had the most impact on the input capacitor. The input filter inductor is basically a straightforward design. There are four parameters required to achieve a good design: required inductance, dc current, dc resistance, and temperature rise. The input filter can affect the stability of the associated switching converter. The stability problem results from an interaction between the output impedance of the input filter and the input impedance of the switching converter. Oscillation occurs when the combined positive resistance of the LC filter, and power source exceed the negative dynamic resistance of the regulator’s dc input. Most all types of electronic equipment are energized by either a switch or relay. This type of turn-on goes for spacecraft, aircraft, computer, medical equipment, and automobiles.
