The uncontrolled electronic switch employed in power-electronic converters is

In series connection, thyristor having the highest leakage resistance or low voltage current will share

UJT oscillators are used for gate-triggering of thyristors for

In a GTO, anode current begins to fall when gate current

The normal way to close a SCR is by

If gate current is increased, the anode-cathode voltage at which SCR closes is

In a GTO, anode current begins to fall when gate current

Which of the following conditions is necessary for triggering system for thyristors?

When transistors are used in series or parallel, a snubber circuit is used to

Optocouplers combine

As compared to UJT, SUS

The device which cannot be triggered by voltage of either polarity is

In a UJT, maximum value of charging resistance is associated with

A conducting SCR can be opened by reducing __________ to zero.

Which semiconductor power device out of the following is not a current trig- gered device?

Derating factors for parallel connection of thyristors are normally in the range

A device that does not exhibit negative resistance characteristic is

When a UJT is used for triggering of an SCR, the waveshape of the voltage is a

A UJT has one base resistance of 5.2 k. Its intrinsic stand of ratio is 0.67. The inter-base voltage of 12 V is applied across the two passes. The value of base current will be