3KP28 Equivalent & Substitute Parts

Part Overview

The 3KP28 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. It features a 28V reverse standoff voltage with a 3000W peak pulse power rating and operates across the temperature range of -55°C to 175°C. The part is packaged in a P600 axial through-hole configuration and is ROHS3 compliant.

The 3KP28 is classified as obsolete. Equivalent and substitute parts are necessary to maintain design continuity and ensure component availability for new production runs and field replacements.

Substiute Parts

3KP28

Littelfuse Inc.In Stock: 8593KP28 Datasheet

Current PartRFQ

5KP28A

Littelfuse Inc.In Stock: 149105KP28A Datasheet

DirectRFQ

3KP28A-TP

Micro Commercial CoIn Stock: 19123KP28A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP28 is determined by the following critical parameters:

• Voltage - Reverse Standoff: Must be 28V
• Type: Must be Zener diode
• Unidirectional Channels: Must be 1
• Mounting Type: Must be Through Hole
• Operating Temperature Range: Must support -55°C ~ 175°C (TJ)
• Applications: General Purpose

Substitute parts must maintain electrical compatibility within the specified voltage and current ratings while supporting the same operating temperature range. Package variations (P600 vs. R-6) are permissible provided the axial through-hole mounting configuration is preserved and the part can be physically integrated into existing PCB designs.

Parameter Comparison

Engineering Selection Recommendations

The 5KP28A (Littelfuse Inc.) is the primary direct substitute for the 3KP28. Both parts share identical reverse standoff voltage (28V), operating temperature range (-55°C ~ 175°C), and axial through-hole P600 packaging. The 5KP28A is currently in active production status and maintains ROHS3 compliance. The 5KP28A provides enhanced performance with 5000W peak pulse power compared to the 3KP28's 3000W rating, making it suitable for applications requiring higher transient energy dissipation.

The 3KP28A-TP (Micro Commercial Co) is an alternative substitute with equivalent reverse standoff voltage (28V) and operating temperature range. This part maintains the same 3000W power rating as the original 3KP28 and is ROHS3 compliant with active product status. The 3KP28A-TP uses an R-6 axial package instead of P600; physical board layout verification is required to confirm compatibility with existing PCB footprints.

Both substitute parts are ROHS3 compliant and support the full operating temperature range of the original component.

Frequently Asked Questions (FAQ)

Q: Can the 5KP28A replace the 3KP28 in existing designs?

A: Yes. The 5KP28A maintains the critical electrical parameters: 28V reverse standoff voltage, identical operating temperature range (-55°C ~ 175°C), and through-hole axial mounting in P600 package. The increased power rating (5000W vs. 3000W) provides enhanced protection capability without compromising compatibility.

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

A: Both are axial through-hole packages for unidirectional TVS diodes. P600 and R-6 represent different physical form factors. The 3KP28A-TP uses R-6 packaging. PCB footprint compatibility must be verified before substitution, as lead spacing and body dimensions may differ.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. Both the 5KP28A and 3KP28A-TP are ROHS3 compliant, matching the compliance status of the original 3KP28.

Q: Why is the 3KP28 marked as obsolete?

A: The 3KP28 is no longer in active production. The 5KP28A and 3KP28A-TP are active alternatives that provide equivalent or enhanced functionality for new designs and field replacements.

Q: What are the key parameters that determine substitution eligibility?

A: Reverse standoff voltage (28V), zener type, unidirectional channel configuration (1), through-hole mounting, and operating temperature range (-55°C ~ 175°C) are the primary criteria. Clamping voltage and peak pulse current must be evaluated against application requirements.