IE part A 2

A thyristor (SCR) is a

• P-N-P device

• N-P-N device

• P-N-P-N device

• P-N device

Which terminal does not belong to the SCR?

• Anode

• Gate

• Base

• Cathode

An SCR is a

• four layer, four junction device

• four layer, three junction device

• four layer, two junction device

• three layer, single junction device

Choose the false statement

• SCR is a bidirectional device

• SCR is a controlled device

• In SCR the gate is the controlling terminal

• SCR are used for high-power applications

In the SCR structure the gate terminal is located

• near the anode terminal

• near the cathode terminal

• in between the anode & cathode terminal

• none of the mentioned

Among the following, the most suitable method to turn on the SCR device is the

• gate triggering method

• dv/dt triggering method

• forward voltage triggering method

• temperature triggering method

Usually the forward voltage triggering method is not used to turn-on the SCR because

• it increases losses

• it causes noise production

• it may damage the junction & destroy the device

• relatively it’s an inefficient method

The value of anode current required to maintain the conduction of an SCR even though the gate signal is removed is called as the

• holding current

• latching current

• switching current

• peak anode current

The minimum value of anode current below which it must fall to completely turn-off the device is called as the

• holding current value

• latching current value

• switching current value

• peak anode current value

The latching current is _________ than the holding current

• lower

• higher

• same as

• negative of