Switching regulators, due to their high power conversion efficiency and flexibility, have made inroads into a growing number of devices and become the preferred power supply units. Previously, a standard practice for switching power supply units was to purchase completed modules or units. In recent years, however, with the availability of ICs for a wide variety of switching power supplies, the strategy employed by electric circuit designers has shifted to the so-called “on-board design” in which a switching power supply unit is built into the circuit board. That said, it is also a fact of life that the various issues presented by switching power circuits, different from the linear regulator, pose a significant challenge to the designer.
In this installment, focusing on the step-down switching regulator, its basic aspects, such as its operation and functions are explained.