Electronics - Thyristors and Tranducers - Discussion

My answer is C. Low Current Dropout.

The only way to close the SCR is when the current goes below the holding current. I see it as the best answer.

Unless the "close" in the question means "closing the switch" which is effectively turning on the SCR then it's a misleading question because using close instead of short in engineering is faulty.

SCR's can also be triggered by increasing the forward voltage beyond their rated breakdown voltage (also called as break over voltage) , but again, this does not rapidly switch the entire device into conduction and so may be harmful so this mode of operation is also usually avoided. Also, the actual breakdown voltage may be substantially higher than the rated breakdown voltage, so the exact trigger point will vary from device to device. A uni-junction transistor is commonly used to trigger SCR.

What is break over voltage?

Break over Voltage is the minimum reverse voltage to make the diode conduct in reverse.

Option C.

As the current decreases below holding value, the SCR will turn off.

Forward break over voltage cannot be the answer because it is the minimum voltage at which SCR switches on.

My answer is C. Low Current Dropout.

The only way to close the SCR is when the current goes below the holding current. I see it as the best answer.

Unless the "close" in the question means "closing the switch" which is effectively turning on the SCR then it's a misleading question because using close instead of short in engineering is faulty.