3KP20A-B Transient Voltage Suppressor Equivalent & Substitute Parts

Part Overview

The 3KP20A-B is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features a 20V reverse standoff voltage with a 32.4V maximum clamping voltage and 92.6A peak pulse current capability in a through-hole P600 axial package. The 3KP20A-B is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Suitable alternatives maintain the same electrical performance envelope while offering active product status and improved availability.

Substiute Parts

3KP20A-B

Littelfuse Inc.In Stock: 11493KP20A-B Datasheet

Current PartRFQ

5KP20A-B

Littelfuse Inc.In Stock: 9635KP20A-B Datasheet

DirectRFQ

3KP20A-TP

Micro Commercial CoIn Stock: 13103KP20A-TP Datasheet

MFR RecommendedRFQ

5KP20A-TP

Micro Commercial CoIn Stock: 10335KP20A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3KP20A-B is determined by strict equivalence across the following electrical and mechanical parameters:

• Voltage - Reverse Standoff: 20V (exact match required)
• Voltage - Clamping (Max) @ Ipp: 32.4V (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: P600 or R-6 Axial (compatible geometries)
• Operating Temperature Range: -55°C to 175°C (exact match required)
• RoHS Status: ROHS3 Compliant (compliance requirement)

The 5KP20A-B and 5KP20A-TP variants are qualified substitutes despite higher peak pulse current (157.4A vs. 92.6A) and power dissipation (5000W vs. 3000W) because these parameters represent enhanced performance within the same voltage class and package family. The 3KP20A-TP variant maintains identical electrical specifications with compatible R-6 axial packaging.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 5KP20A-B (Littelfuse Inc.)

The 5KP20A-B is the direct manufacturer equivalent with active product status. It maintains identical voltage specifications (20V standoff, 32.4V clamping) and operating temperature range while providing enhanced current handling (157.4A vs. 92.6A) and power dissipation (5000W vs. 3000W). This higher performance envelope ensures compatibility with the original 3KP20A-B application while offering superior transient protection margin. ROHS3 compliance and through-hole P600 axial packaging provide direct mechanical and environmental compatibility.

Secondary Substitute: 3KP20A-TP (Micro Commercial Co)

The 3KP20A-TP maintains identical electrical specifications to the 3KP20A-B with active product status. Manufacturer recommendation by Micro Commercial Co confirms engineering equivalence. The R-6 axial package is mechanically compatible with P600 footprints in standard through-hole applications. ROHS3 compliance and REACH unaffected status satisfy regulatory requirements.

Tertiary Substitute: 5KP20A-TP (Micro Commercial Co)

The 5KP20A-TP combines the performance enhancement of the 5KP series with active product status and manufacturer recommendation. It provides the same voltage class as the 3KP20A-B with increased current and power handling. R-6 axial packaging is mechanically compatible with standard through-hole layouts.

All substitute parts maintain ROHS3 compliance and Moisture Sensitivity Level 1 (unlimited shelf life), ensuring regulatory and environmental compatibility with the original component.

Frequently Asked Questions (FAQ)

Q: Can the 5KP20A-B replace the 3KP20A-B in existing designs?

A: Yes. The 5KP20A-B maintains identical voltage specifications (20V standoff, 32.4V clamping) and operating temperature range. The higher peak pulse current (157.4A vs. 92.6A) and power dissipation (5000W vs. 3000W) represent enhanced performance within the same voltage class. Through-hole P600 axial packaging provides direct mechanical compatibility.

Q: What is the difference between P600 and R-6 axial packages?

A: Both P600 and R-6 are through-hole axial package formats for TVS diodes. R-6 represents a compatible alternative geometry suitable for standard through-hole PCB layouts. Mechanical compatibility is maintained for typical circuit board applications.

Q: Are the Micro Commercial Co variants (3KP20A-TP, 5KP20A-TP) equivalent to Littelfuse parts?

A: Yes. The 3KP20A-TP and 5KP20A-TP are manufacturer-recommended equivalents with identical electrical specifications. Both maintain ROHS3 compliance and active product status. Packaging differences (R-6 vs. P600) do not affect electrical performance or circuit compatibility.

Q: Why is the 3KP20A-B classified as obsolete?

A: Obsolete status indicates the part is no longer manufactured by Littelfuse Inc. Active alternatives (5KP20A-B, 3KP20A-TP, 5KP20A-TP) provide equivalent or enhanced performance with current availability and manufacturer support.

Q: Can I use a higher power-rated TVS diode as a substitute?

A: Yes, within the same voltage class. The 5KP20A-B and 5KP20A-TP provide higher power dissipation (5000W vs. 3000W) while maintaining identical voltage specifications. This represents a performance upgrade suitable for applications requiring enhanced transient protection.

Q: Are all substitute parts RoHS compliant?

A: Yes. All listed substitute parts (5KP20A-B, 3KP20A-TP, 5KP20A-TP) are ROHS3 compliant, matching the environmental compliance of the original 3KP20A-B.