Evaluate the statement: Thyristors are not suitable for logic circuits.

Introduction / Context:
Logic circuits require devices that switch very rapidly, consume minimal static power, and can be reset or toggled predictably by small signals. Thyristors, including SCRs, are latching power devices optimized for high current and voltage control, not for digital logic switching at low power levels.

Given Data / Assumptions:

• Thyristor characteristics: latching behavior, needs current to fall below holding current to turn off.
• Logic circuit needs: fast switching, non-latching control, low drive and low power.
• Typical frequency and voltage levels of logic are far lower than power electronics levels.

Concept / Approach:

An SCR turns on with a gate trigger but turns off only when the anode current drops below the holding current. This inherent latching makes it unsuitable for general logic where devices must both turn on and off by gate or base control at will. Additionally, thyristors have relatively slow switching times compared with transistors and CMOS devices used in logic gates.

Step-by-Step Reasoning:

Verification / Alternative check:

Digital electronics uses BJT, MOSFET, and CMOS devices in TTL/CMOS families. Thyristors are found in rectifiers, inverters, choppers, and motor drives, not in logic ICs.

Why Other Options Are Wrong:

• False: contradicts the fundamental latching and slow turn-off characteristics.
• Depends on supply or temperature only: suitability is rooted in device physics, not just operating conditions.
• Only true at high frequency: even at low frequency, the inability to gate turn-off is a problem for logic.

Common Pitfalls:

• Confusing TRIAC or SCR triggering with logic-level control capability.
• Assuming any three-terminal device is automatically logic-suitable.

Final Answer:

True