SCR package styles and typical current ratings Lead-mounted SCR packages are typically used for which approximate current rating range?

Introduction / Context:
Silicon controlled rectifiers (SCRs) are available in different package styles suited to different current ranges. Choosing the right package is essential for thermal management and mounting.

Given Data / Assumptions:

• Lead-mounted (axial/through-hole) small-outline SCRs are intended for low currents.
• Stud-mount and press-pack (capsule) suit higher currents due to better heat sinking.

Concept / Approach:
Package capability is largely set by thermal resistance and allowable junction temperature rise. Lead-mounted devices have limited heat dissipation relative to stud or press-pack types.

Step-by-Step Solution:
Identify typical lead-mounted capability → around hundreds of milliamperes up to roughly 1 A.Compare to stud-mount (often 10 A to hundreds of amperes) and press-pack (high tens to kiloampere-class).Therefore, the closest correct band is about 1 A or less.

Verification / Alternative check:
Check SCR datasheets: small axial devices are commonly rated sub-ampere to about 1 A continuous, aligning with the above.

Why Other Options Are Wrong:
Less than a few mA: Unrealistically low for SCR usefulness.
20 A/100 A/500 A: These ratings require robust thermal paths beyond simple lead mounting.

Common Pitfalls:
Assuming physical size alone dictates rating; thermal path and package mounting method are decisive.

Final Answer:
about 1 A or less