what is latching current in scr

Latching current in an SCR (Silicon Controlled Rectifier) is the minimum current required to maintain the SCR in the ON state immediately after it has been turned on and the gate signal has been removed. In other words, it is the minimum additional current that can make up for any missing input (gate) current in order to keep the device ON). On the other hand, holding current is the minimum anode current required to maintain the SCR in the ON state. It is the minimum value of current below which anode current must fall to come in the OFF state. Therefore, latching current is related to the turn-on process of the SCR, while holding current is related to the turn-off process of the SCR.