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For an SCR, during turn-on and turn-off, the quantities responsible, respectively are

For an SCR, during turn-on and turn-off, the quantities responsible, respectively are Correct Answer latching current and holding current

Latching Current:

  • Latching current of forward biased SCR is the minimum current which anode current must attain to continue to remain in forward conduction mode even when gate current is removed.
  • If the value of anode current is less than this value, then the SCR will not continue to conduct in forward direction if gate signal is removed.
  • But once anode current becomes more than latching current, gate losses its control and gate signal may be removed and SCR will continue to conduct.
  • Hence, latching current is related with turn on process of the SCR


Holding Current:

  • Holding current of SCR is that minimum value of current below which anode current must fall to come in OFF state.
  • Holding current is related with turn off process of the SCR.


Value of latching current is more than that of holding current for the SCR.

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