3KP8.5 Transient Voltage Suppressor Equivalent & Substitute Parts

Part Overview

The 3KP8.5 is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features an 8.5V reverse standoff voltage with a 15.12V maximum clamping voltage and 208.3A peak pulse current capability in a through-hole P600 axial package.

The 3KP8.5 is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs, repairs, and system upgrades.

Substiute Parts

3KP8.5

Littelfuse Inc.In Stock: 11493KP8.5 Datasheet

Current PartRFQ

5KP8.5A

LittelfuseIn Stock: 3001105KP8.5A Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 3KP8.5 are identified based on the following critical electrical and mechanical parameters:

• Voltage - Reverse Standoff (Typ): 8.5V
• Unidirectional Zener TVS diode configuration
• Through-hole P600 axial package
• Operating temperature range: -55°C ~ 175°C
• RoHS3 compliance and MSL Level 1 rating

The 5KP8.5A qualifies as a direct substitute because it maintains the same reverse standoff voltage (8.5V), unidirectional Zener type, P600 axial package, and thermal operating range. While the 5KP8.5A offers higher peak pulse current (354.2A) and peak pulse power (5000W) compared to the 3KP8.5 (208.3A, 3000W), these represent enhanced performance characteristics that do not compromise compatibility in applications designed for the original part.

Parameter Comparison

Engineering Selection Recommendations

The 5KP8.5A is the qualified substitute for the obsolete 3KP8.5. Both components share identical reverse standoff voltage (8.5V), unidirectional Zener configuration, P600 axial package geometry, and thermal operating range (-55°C ~ 175°C). Both components maintain ROHS3 compliance and MSL Level 1 rating.

The 5KP8.5A is currently in active production status with substantial inventory availability (300,100 pcs), whereas the 3KP8.5 is obsolete with limited remaining stock (1,120 pcs). The 5KP8.5A provides enhanced electrical performance with higher peak pulse current (354.2A vs. 208.3A) and peak pulse power (5000W vs. 3000W), making it suitable for applications requiring the original 3KP8.5 specifications and for designs benefiting from increased transient protection margin.

Frequently Asked Questions (FAQ)

Q: Can the 5KP8.5A directly replace the 3KP8.5 in existing circuit designs?

A: Yes. Both components share the same reverse standoff voltage (8.5V), unidirectional Zener type, P600 axial through-hole package, and operating temperature range. The 5KP8.5A's higher peak pulse current and power ratings represent enhanced performance that does not introduce compatibility issues.

Q: What are the key differences between the 3KP8.5 and 5KP8.5A?

A: The primary differences are product status (3KP8.5 is obsolete; 5KP8.5A is active), peak pulse current (208.3A vs. 354.2A), and peak pulse power (3000W vs. 5000W). The voltage characteristics (reverse standoff, breakdown, and clamping) remain within compatible ranges.

Q: Are both components available in the same package?

A: Yes. Both the 3KP8.5 and 5KP8.5A use the P600 axial through-hole package, ensuring mechanical and electrical compatibility on printed circuit boards.

Q: Do both components meet the same compliance standards?

A: Yes. Both components are ROHS3 compliant with MSL Level 1 (Unlimited) moisture sensitivity rating, meeting equivalent environmental and regulatory requirements.

Q: Why is the 5KP8.5A rated for higher peak pulse power?

A: The 5KP8.5A is designed with enhanced transient suppression capability. The higher peak pulse current (354.2A) and power rating (5000W) reflect improved performance characteristics within the same package form factor.