forward-blocking state

The term "forward-blocking state" refers to a condition in certain electronic components, particularly thyristors, where they block the flow of current. A thyristor is a semiconductor device with two stable states: an "off" state (high resistance, low current) and an "on" state (low resistance, high current).1

In the forward-blocking state, the thyristor acts like an insulator, preventing current from passing through it. This state is maintained until a specific voltage, known as the forward-breakover voltage, is reached, or until a signal is applied to a control electrode called the gate. When triggered, the thyristor switches to its conducting "on" state.1

This behavior is analogous to a diode, which is a two-terminal electronic component that primarily allows current to flow in only one direction. A common type of diode uses a p-n junction. When this junction is reverse-biased, it blocks current flow. However, when forward-biased, it allows current to pass.234