Littelfuse 5KP8.5 Transient Voltage Suppressor Equivalent & Substitute Parts

Part Overview

The Littelfuse 5KP8.5 is a unidirectional Zener transient voltage suppressor (TVS) diode designed for general-purpose overvoltage protection applications. This component features an 8.5V reverse standoff voltage rating with 5000W peak pulse power handling capability in a through-hole P600 axial package. The 5KP8.5 is classified as obsolete, necessitating identification of active equivalent and substitute parts for new designs and ongoing production requirements. Suitable alternatives must maintain electrical compatibility across voltage ratings, power dissipation, and mechanical form factors while meeting current RoHS3 compliance standards.

Substiute Parts

5KP8.5

Littelfuse Inc.In Stock: 8095KP8.5 Datasheet

Current PartRFQ

5KP8.5A

LittelfuseIn Stock: 3001105KP8.5A Datasheet

DirectRFQ

SA8.5A

Taiwan Semiconductor CorporationIn Stock: 8461SA8.5A Datasheet

MFR RecommendedRFQ

5KP8.5E3/TR13

Microchip TechnologyIn Stock: 12205KP8.5E3/TR13 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 5KP8.5 is determined by the following critical parameters: voltage rating (8.5V reverse standoff with 8.93V minimum breakdown), unidirectional channel configuration, power dissipation capacity (5000W peak pulse), through-hole mounting, and RoHS3 compliance. Substitute parts must maintain the same voltage class and unidirectional topology to ensure functional equivalence in overvoltage protection circuits.

Three active alternatives are identified:

5KP8.5A (Littelfuse) — Direct manufacturer successor with identical voltage ratings and 5000W power rating. Supplied in tape and reel packaging with active product status.

5KP8.5E3/TR13 (Microchip Technology) — Functionally equivalent with matching voltage standoff and breakdown specifications, 5000W power rating, and P600 package. Supplied in tape and reel format with active status.

SA8.5A (Taiwan Semiconductor Corporation) — Alternative topology using DO-204AC (DO-15) package instead of P600. Maintains 8.5V voltage rating and 14.4V clamping voltage but with reduced 500W peak pulse power rating. Suitable only for lower-power applications.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Full Compatibility): The 5KP8.5A and 5KP8.5E3/TR13 are direct functional equivalents with active product status and full RoHS3 compliance. Both maintain the P600 axial package, 5000W power rating, and 8.5V voltage class. Selection between these two depends on supplier availability and lead time. The 5KP8.5A represents the direct Littelfuse successor, while the 5KP8.5E3/TR13 offers Microchip sourcing as an alternative.

Secondary Substitute (Power-Limited Applications): The SA8.5A is suitable only for applications where peak pulse power requirements do not exceed 500W. This part uses the DO-204AC package instead of P600, requiring PCB layout modification. The reduced power rating and different package form factor make this option applicable only to lower-power overvoltage protection circuits.

All substitutes maintain RoHS3 compliance, unlimited moisture sensitivity rating (MSL 1), and the required -55°C to 175°C operating temperature range.

Frequently Asked Questions (FAQ)

Q: Can the SA8.5A directly replace the 5KP8.5 in existing designs?

A: The SA8.5A is electrically compatible for voltage protection but has a reduced 500W peak pulse power rating compared to the 5000W rating of the main part. Additionally, the DO-204AC package differs from the P600 package, requiring PCB layout changes. Use SA8.5A only if your application power requirements are confirmed below 500W and board redesign is acceptable.

Q: What is the difference between the 5KP8.5A and 5KP8.5E3/TR13?

A: Both parts maintain identical voltage ratings (8.5V standoff), 5000W power dissipation, and P600 axial packaging. The primary differences are manufacturer (Littelfuse vs. Microchip) and minor variations in clamping voltage (14.4V vs. 15.9V) and peak pulse current specifications. Either part provides full functional equivalence for the obsolete 5KP8.5.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. The 5KP8.5A, 5KP8.5E3/TR13, and SA8.5A are all ROHS3 Compliant with MSL 1 (Unlimited) moisture sensitivity rating, matching the compliance profile of the original 5KP8.5.

Q: What packaging formats are available for these substitutes?

A: The 5KP8.5A and 5KP8.5E3/TR13 are supplied in tape and reel (TR) format for automated assembly. The SA8.5A is also available in tape and reel packaging. All three maintain through-hole mounting compatibility with standard PCB assembly processes.

Q: Which substitute should I select for new production designs?

A: For new designs requiring full 5000W power handling and P600 package compatibility, select either the 5KP8.5A or 5KP8.5E3/TR13 based on supplier availability and lead time. Both offer active product status and equivalent electrical performance. For applications with confirmed power requirements below 500W, the SA8.5A provides an alternative sourcing option.