SMD, an acronym for Surface-Mount Device, is a type of electronic component that is mounted directly onto the surface of a printed circuit board (PCB) without the use of leads or wires. This method of mounting is known as surface mount technology (SMT).
SMDs are typically small in size and have a flat profile, which allows them to be placed close together on a PCB, resulting in a higher component density and smaller overall board size. This compact design is ideal for electronic devices that are becoming increasingly smaller and more powerful.
SMDs offer a range of advantages over traditional leaded components, including improved electrical performance, higher reliability, and easier assembly. Additionally, SMDs are more resistant to shock and vibration, which is important for applications where durability is a concern. The transition to SMDs has been driven by several factors, including the miniaturization of electronic devices, the increasing use of high-speed digital circuits, and the need for improved reliability.