SCR will be turned off when anode current is < latching current but greater than holding current and gate signal is 0. both (A) and (B). < latching current but greater than holding current and gate signal is present. less than holding current. TRUE ANSWER : ? YOUR ANSWER : ?
During which time maximum conduction spreading take place in the thyristor during turn ON? Delay time. Same for every case. Spread time. Rise time. TRUE ANSWER : ? YOUR ANSWER : ?
A modern power semiconductor device that combines the characteristic of BJT and MOSFET is MCT. IGBT. GTO. FCT. TRUE ANSWER : ? YOUR ANSWER : ?
A UJT is sometimes called ___________ diode. High resistance Low resistance Double-base Single-base TRUE ANSWER : ? YOUR ANSWER : ?
The capacitance of reversed bised junction J2 in a thyristor is CJ2 = 20 pF and can be assumed to be independant of the off state voltage. The limiting value of the charging current to turn on the thyristor is 16 mA. What is the critical value of dv/dt? 1200 V/µs. 800 V/µs. 600 V/µs. 1000 V/µs. TRUE ANSWER : ? YOUR ANSWER : ?
Maximum di / dt in a SCR is directly proportional to Vm of supply voltage. both A and C. inversely proportional to L in the circuit. inversely proportional to Vm of supply voltage. TRUE ANSWER : ? YOUR ANSWER : ?
How can we protect SCR from thermal conditions ? Use of snubber circuit. Using heat sink. Using equalizing circuit. Using CB and fuse. TRUE ANSWER : ? YOUR ANSWER : ?
For an SCR gate cathode characteristic is a straight line of 130. For triggered source volume of 15 V and allowable gate power dissipation of 0.5 W compute the gate source resistance? 11.19 ohm 108 ohm 111.9 ohm 115 ohm TRUE ANSWER : ? YOUR ANSWER : ?
When the temperature increases, the inter-base resistance (RBB) of a UJT ___________. Decreases None of these Remains the same Increases TRUE ANSWER : ? YOUR ANSWER : ?
The triac is ___________. A four-terminal device Not a thyristor None of these Like a bidirectional SCR TRUE ANSWER : ? YOUR ANSWER : ?