3KP24CA-B Equivalent & Substitute Parts

Part Overview

The 3KP24CA-B is a bidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features a 24V reverse standoff voltage with a 38.9V maximum clamping voltage and 77.1A peak pulse current capability in a P600 axial through-hole package. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations.

Substiute Parts

3KP24CA-B

Littelfuse Inc.In Stock: 11253KP24CA-B Datasheet

Current PartRFQ

5KP24CA-B

LittelfuseIn Stock: 11795KP24CA-B Datasheet

DirectRFQ

SA24CA

Fairchild SemiconductorIn Stock: 4653SA24CA Datasheet

MFR RecommendedRFQ

15KP24CA-TP

Micro Commercial CoIn Stock: 116015KP24CA-TP Datasheet

MFR RecommendedRFQ

3KP24CA-TP

Micro Commercial CoIn Stock: 10683KP24CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP24CA-B is determined by the following critical parameters:

• Voltage - Reverse Standoff: 24V (exact match required)
• Voltage - Breakdown (Min): 26.7V (exact match required)
• Voltage - Clamping (Max) @ Ipp: 38.9V (tolerance range acceptable)
• Operating Temperature Range: -55°C ~ 175°C (exact match required)
• Type: Zener, Bidirectional (exact match required)
• RoHS Compliance: ROHS3 Compliant (required for regulatory alignment)

Substitute parts are grouped into two categories based on package compatibility and electrical performance:

Category A - Same Package (P600): Parts maintaining identical P600 axial through-hole packaging with matching electrical specifications.

Category B - Alternative Package (R-6, DO-204AC): Parts with equivalent electrical performance but different through-hole package configurations, requiring PCB layout modification.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 5KP24CA-B

The 5KP24CA-B is the recommended direct substitute for the 3KP24CA-B. Both parts share identical voltage specifications (24V reverse standoff, 26.7V breakdown minimum, 38.9V clamping maximum) and maintain the same P600 axial through-hole package. The 5KP24CA-B is currently in active product status with ROHS3 compliance. The increased peak pulse current (131.1A versus 77.1A) and power rating (5000W versus 3000W) provide enhanced transient protection capability without compromising compatibility. No PCB layout modifications are required.

Secondary Substitute: 3KP24CA-TP

The 3KP24CA-TP, manufactured by Micro Commercial Co, provides electrical equivalence with identical voltage and current specifications (24V standoff, 38.9V clamping, 77.1A peak pulse). This part is currently active and ROHS3 compliant. The package differs (R-6 versus P600), requiring PCB footprint modification. This option is suitable when component sourcing from alternative manufacturers is necessary.

Alternative Substitute: 15KP24CA-TP

The 15KP24CA-TP offers the highest power dissipation capability (15000W) among available substitutes while maintaining the 24V voltage class. The clamping voltage is 40.5V, which falls within acceptable tolerance for general-purpose applications. This part is active and ROHS3 compliant. The R-6 package requires PCB layout modification. Selection of this part is appropriate for applications requiring maximum transient energy absorption.

Not Recommended: SA24CA

The SA24CA, manufactured by Fairchild Semiconductor, is classified as obsolete and features significantly reduced peak pulse current (13.1A) and power rating (500W) compared to the 3KP24CA-B. The DO-204AC package differs from the original P600 configuration. This part does not provide adequate performance for applications requiring the original 77.1A pulse current capability.

Frequently Asked Questions (FAQ)

Q: Can the 5KP24CA-B directly replace the 3KP24CA-B without PCB modifications?

A: Yes. Both parts use the P600 axial through-hole package with identical pinout and footprint. No PCB layout changes are required. The 5KP24CA-B is a direct mechanical and electrical substitute.

Q: What is the significance of the higher current rating in the 5KP24CA-B?

A: The 5KP24CA-B handles 131.1A peak pulse current versus 77.1A in the 3KP24CA-B. This increased capability provides enhanced protection margin for transient overvoltage events without changing the voltage regulation characteristics. The part remains compatible with existing circuit designs.

Q: Why is the SA24CA not recommended as a substitute?

A: The SA24CA has a peak pulse current rating of only 13.1A and power dissipation of 500W, substantially below the 3KP24CA-B specifications of 77.1A and 3000W. This reduced capability makes it unsuitable for applications designed around the original part's performance envelope.

Q: Can I use the 15KP24CA-TP if I modify my PCB for the R-6 package?

A: Yes. The 15KP24CA-TP meets all voltage specifications and is currently active with ROHS3 compliance. The R-6 package requires PCB footprint modification. The 40.5V clamping voltage is within acceptable tolerance for the 24V voltage class. This option is suitable when maximum transient energy absorption is required.

Q: Are all substitute parts ROHS3 compliant?

A: All active substitute parts listed (5KP24CA-B, 3KP24CA-TP, 15KP24CA-TP) are ROHS3 compliant, matching the regulatory status of the original 3KP24CA-B.

Q: What is the primary difference between the 3KP24CA-B and 3KP24CA-TP?

A: Both parts have identical electrical specifications (24V standoff, 38.9V clamping, 77.1A peak pulse, 3000W power). The primary difference is the package: 3KP24CA-B uses P600 while 3KP24CA-TP uses R-6. The 3KP24CA-TP is currently active, whereas the 3KP24CA-B is obsolete.