Question

Turn-on time of an SCR can be reduced by using a _______.

• A. rectangular pulse of high amplitude and narrow width
• B. rectangular pulse of low amplitude and wide width
• C. triangular pulse
• D. trapezoidal pulse

Hint:

To reduce SCR turn-on time → use a sharp rectangular pulse with high amplitude.

Answer 1

The Correct Option is A

Step 1: Understand SCR Turn-On
SCR (Silicon Controlled Rectifier) turns on when gate current exceeds a threshold. Faster turn-on means quicker transition to conduction mode.
Step 2: Factors Affecting Turn-On Time
- High gate amplitude → faster triggering
- Narrow pulse → minimizes power consumption
Step 3: Why Rectangular Pulse?
- Provides a sudden strong gate current
- Leads to rapid formation of conduction path
Conclusion:
Option (1) is correct — narrow high amplitude pulse minimizes turn-on delay.