Power semiconductor devices – Match each device class to a typical maximum practical switching frequency List I (Power device) A. Power bipolar transistor B. Power MOSFET C. SCR (thyristor) D. IGBT (insulated-gate bipolar transistor) List II (Typical max frequency order) MHz 100 kHz 10 kHz 1 kHz Select the correct mapping.

Introduction / Context:
In power electronics, device physics limits switching speed. Remembering the rough frequency order helps pick devices for converters, motor drives, and RF power stages.

Given Data / Assumptions:

• Power MOSFETs can reach into the MHz range (low voltage types).
• IGBTs are typically comfortable to tens of kHz (≈100 kHz upper practical bound for fast modules).
• Power BJTs switch slower than MOSFETs, around the 10 kHz order.
• SCRs are the slowest for high-power switching (≈1 kHz order) due to turn-off limitations (unless special commutation).

Concept / Approach:

Map each class to its typical maximum practical switching frequency in power applications: BJT → ~10 kHz; MOSFET → MHz; SCR → ~1 kHz; IGBT → ~100 kHz.

Step-by-Step Solution:

Verification / Alternative check:

Application notes from device vendors show MOSFETs used at hundreds of kHz to MHz, IGBTs tens of kHz, BJTs slower, and SCRs at line-commutated or low switching frequencies.

Why Other Options Are Wrong:

Swapping MOSFET and SCR contradicts practical converter designs; assigning MHz to IGBTs is atypical.

Common Pitfalls:

Ignoring voltage/current rating dependence on speed; very high-voltage MOSFETs may be slower than low-voltage types.

Final Answer:

A-3, B-1, C-4, D-2.