What distinguishes an SCR from a standard diode?

An SCR, or Silicon Controlled Rectifier, is characterized by having three terminals: anode, cathode, and gate. This is a fundamental distinction from a standard diode, which only has two terminals (anode and cathode). The gate terminal in an SCR allows for control over its conduction state, meaning that it can be switched on and off, which is not a feature of standard diodes.

The ability to control the SCR with the gate terminal adds complexity and makes it suitable for various applications in power control and switching. This three-terminal configuration allows for greater flexibility in circuit design and operation compared to standard diodes.

In summary, the three-terminal structure of an SCR is essential for its functionality and differentiates it from standard diodes.