Which statement is true regarding the relationship between gate signal duration and SCR operation?

The statement about the relationship between gate signal duration and SCR operation highlights the fundamental function of a silicon-controlled rectifier (SCR). When an SCR is triggered by a gate signal, it enters the conduction state and remains conducting as long as the current flowing through it (the anode current) exceeds the holding current.

The duration and strength of the gate signal essentially influence how effectively the SCR turns on. A longer gate signal ensures that the SCR is fully turned on, allowing a larger amount of load current to flow through it. This increased duration helps maintain the conductive state even as the gate current dissipates, leading to the SCR remaining on for a longer period after the gate signal is removed, as long as the conditions for conduction (like the anode current exceeding holding current) are met.

In contrast, a shorter gate signal may not provide sufficient drive to ensure that the SCR remains genuinely turned on, which could result in it turning off more quickly or not fully entering the conduction state at all. Therefore, the relationship is such that a longer gate signal correlates directly with an extended time that the SCR remains in an on state after the signal is applied.