Buck converter or Step down converter:
Buck converter is a step-down converter. The buck converter step-down the output voltage and step up the output current. Buck converter is a DC to DC converter. The buck converter basically consists of a transistor for switching purpose, diode, inductor, and capacitor. There are two modes in buck converter depending on switching actions of transistor and current flowing through the inductor. One is continuous mode and second is discontinuous mode. Buck converter is used in laptop or computers where voltage step down is needed. Buck converters are used in mobile phones. Buck converter is a non-isolated type of DC to DC converter. When the transistor (switch) is in on state then current flows through inductor and inductor charges to its peak and when the transistor (switch) is in off state then diode allows the path to current to flow and inductor acts as a source to load. The output voltage is controlled by controlling on period and off period.