ABSTRACT
A diode generally refers to a two-terminal solid-state semiconductor device that presents a low impedance to current flow in one direction and a high impedance to current flow in the opposite direction. Most diodes are made from a host crystal of silicon with appropriate impurity elements introduced to modify, in a controlled manner, the electrical characteristics of the device. These diodes are the typical pn-junction devices used in electronic circuits. Another type is the Schottky diode, produced by placing a metal layer directly onto the semiconductor. The chapter discusses some simple uncontrolled rectifier circuits that are commonly encountered. The term uncontrolled refers to the absence of any control signal necessary to operate the primary switching elements in the rectifier circuit. The discussion of controlled rectifier circuits, and the controlled switches themselves, is more appropriate in the context of power electronics applications.
