Military, MIL-PRF-19500/276 Series, SCRs

Silicon Controlled Rectifiers (SCRs) are electronic devices with three terminals that exhibit behavior similar to rectifier diodes. However, SCRs possess an additional capability—they can block current flow in the forward direction until a control signal is applied. SCRs are widely used for controlling AC utility power and are sometimes referred to as thyristors, although this term can also encompass other related devices. The primary function of an SCR is to regulate the flow of current in electronic circuits. In its default state, the SCR acts as an open circuit, preventing current from passing through in the forward direction. However, once a control signal, typically a pulse, is applied to the gate terminal of the SCR, it switches into a conducting state, allowing current to flow. One of the most common applications of SCRs is in the control of AC utility power. By utilizing SCRs in AC switching circuits, precise control over power delivery can be achieved. This is particularly useful for applications such as motor speed control, lamp dimming, and heating element regulation. The term "thyristor" is often used interchangeably with SCR, referring to the same type of device. However, it is worth noting that in some cases, "thyristor" may be used to describe a broader category of related devices with similar characteristics. In summary, SCRs are three-terminal devices that exhibit rectifier-like behavior while also possessing the ability to block current flow in the forward direction until a control signal is applied. Widely used for controlling AC utility power, SCRs, or thyristors, play a crucial role in achieving precise control over current flow in various electronic applications.