Littelfuse 3KP24A Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The Littelfuse 3KP24A is a unidirectional Zener-type transient voltage suppressor diode 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 3KP24A is classified as obsolete, making identification of functionally equivalent active alternatives essential for ongoing design support and procurement continuity.

Substiute Parts

3KP24A

LittelfuseIn Stock: 7883KP24A Datasheet

Current PartRFQ

5KP24A

Littelfuse Inc.In Stock: 38105KP24A Datasheet

DirectRFQ

3KP24A-TP

Micro Commercial CoIn Stock: 16613KP24A-TP Datasheet

MFR RecommendedRFQ

SA24A-AP

Micro Commercial CoIn Stock: 791SA24A-AP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP24A is determined by the following critical parameters:

• Voltage Rating Match: Reverse standoff voltage of 24V, breakdown voltage minimum of 26.7V, and clamping voltage maximum of 38.9V must remain constant across all substitutes
• Unidirectional Configuration: Single-channel Zener-type topology required
• Through-Hole Mounting: Physical mounting compatibility with axial through-hole PCB layouts
• Operating Temperature Range: Full -55°C to 175°C (TJ) operational capability
• Compliance Status: RoHS3 compliance and MSL Level 1 (Unlimited) moisture sensitivity

The substitute parts identified maintain these core electrical and mechanical parameters while offering variations in peak pulse current capacity, power dissipation, package form factor, and product status.

Parameter Comparison

Engineering Selection Recommendations

5KP24A (Littelfuse Inc.) - Direct electrical equivalent with enhanced performance. Maintains identical voltage ratings and clamping characteristics while providing increased peak pulse current (131.1A vs. 77.1A) and power dissipation (5000W vs. 3000W). Identical P600 axial package ensures direct PCB layout compatibility. Active product status with full RoHS3 compliance and unlimited MSL rating. Suitable for applications requiring equal or greater transient energy absorption capacity.

3KP24A-TP (Micro Commercial Co) - Functional equivalent with identical electrical specifications and power rating (3000W). Maintains 24V voltage rating, 38.9V clamping voltage, and full operating temperature range. Package form factor differs (R-6 axial vs. P600 axial), requiring PCB layout verification for through-hole mounting compatibility. Active product status with RoHS3 compliance and unlimited MSL rating. Appropriate for designs where package footprint variation is acceptable.

SA24A-AP (Micro Commercial Co) - Electrical equivalent with reduced transient energy handling capacity. Maintains identical voltage ratings and clamping characteristics but provides significantly lower peak pulse current (13.1A vs. 77.1A) and power dissipation (500W vs. 3000W). DO-15 axial package represents substantial physical size reduction compared to P600. Active product status with RoHS3 compliance and unlimited MSL rating. Suitable only for low-energy transient suppression applications with reduced surge current requirements.

Frequently Asked Questions (FAQ)

Q: Can the 5KP24A directly replace the 3KP24A in existing designs?

A: Yes. The 5KP24A maintains all critical electrical parameters: 24V reverse standoff voltage, 26.7V minimum breakdown voltage, and 38.9V maximum clamping voltage. The identical P600 axial through-hole package ensures direct PCB compatibility without layout modifications. The increased peak pulse current and power dissipation provide enhanced transient protection margin.

Q: What is the primary difference between the 3KP24A and 5KP24A?

A: Both devices share identical voltage ratings and clamping characteristics. The 5KP24A provides higher peak pulse current capacity (131.1A vs. 77.1A) and greater power dissipation capability (5000W vs. 3000W), enabling protection of higher-energy transient events. The "5K" designation indicates the 5000W power rating versus the "3K" designation for 3000W.

Q: Is the 3KP24A-TP package compatible with P600 PCB footprints?

A: The 3KP24A-TP uses an R-6 axial package rather than P600. While both are through-hole axial configurations, physical dimensions differ. PCB layout verification is required to confirm mounting hole spacing and lead diameter compatibility before substitution.

Q: When should the SA24A-AP be selected over other substitutes?

A: The SA24A-AP is appropriate only for applications with low transient energy requirements. Its 13.1A peak pulse current and 500W power dissipation are substantially lower than the original 3KP24A specification. The DO-15 package provides significant size reduction for space-constrained designs. This substitute is unsuitable for applications requiring the full 77.1A or 3000W protection capability of the original device.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. The 5KP24A, 3KP24A-TP, and SA24A-AP all carry RoHS3 compliance certification. All substitutes maintain MSL Level 1 (Unlimited) moisture sensitivity rating, matching the original 3KP24A specification.

Q: What is the significance of the 3KP24A obsolete status?

A: The 3KP24A is classified as obsolete, indicating Littelfuse has discontinued production and support. The 5KP24A represents the direct Littelfuse successor with enhanced specifications. The 3KP24A-TP and SA24A-AP provide alternative sourcing options from Micro Commercial Co with equivalent or reduced capability profiles.