3KP75-B Equivalent & Substitute Parts

Part Overview

The 3KP75-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features a 75V reverse standoff voltage with a 127.05V maximum clamping voltage and 24.8A peak pulse current capability in a through-hole P600 axial package. The product is currently obsolete, making equivalent substitutes necessary for new designs and ongoing maintenance applications. Substitute parts must maintain electrical compatibility across voltage ratings, clamping characteristics, and thermal operating ranges while accommodating available packaging options.

Substiute Parts

3KP75-B

Littelfuse Inc.In Stock: 8223KP75-B Datasheet

Current PartRFQ

5KP75A-B

Littelfuse Inc.In Stock: 7955KP75A-B Datasheet

DirectRFQ

15KP75A-TP

Micro Commercial CoIn Stock: 70415KP75A-TP Datasheet

MFR RecommendedRFQ

3KP75A-TP

Micro Commercial CoIn Stock: 12223KP75A-TP Datasheet

MFR RecommendedRFQ

5KP75A-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 39885KP75A-E3/54 Datasheet

MFR RecommendedRFQ

5KP75A-TP

Micro Commercial CoIn Stock: 11565KP75A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP75-B is determined by the following critical parameters:

• Voltage - Reverse Standoff (Typ): Must equal 75V
• Voltage - Breakdown (Min): Must fall within 78.93V to 83.3V range
• Voltage - Clamping (Max) @ Ipp: Must not exceed 127.05V
• Current - Peak Pulse (10/1000µs): Must equal or exceed 24.8A
• Power - Peak Pulse: Must equal or exceed 3000W
• Operating Temperature Range: Must support -55°C to 175°C (TJ)
• Type: Must be Zener diode
• Unidirectional Channels: Must equal 1
• Mounting Type: Must be Through Hole
• RoHS Status: Must be ROHS3 Compliant

All qualified substitutes maintain identical reverse standoff voltage and thermal operating range. Package variations (P600 vs. R-6 axial) are acceptable provided board layout accommodates the physical dimensions. Clamping voltage and peak pulse current specifications may vary within acceptable engineering tolerances for the application class.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Recommended for New Designs)

The 3KP75A-TP (Micro Commercial Co) and 5KP75A-E3/54 (Vishay) are the preferred substitutes. Both maintain the 3000W power rating of the original 3KP75-B while offering active product status and full ROHS3 compliance. The 3KP75A-TP matches the exact 24.8A peak pulse current specification, ensuring direct electrical equivalence. The 5KP75A-E3/54 provides enhanced current handling (41.3A) within the same power class, offering design margin for transient protection circuits.

Secondary Substitutes (Higher Power Capability)

The 5KP75A-B and 5KP75A-TP provide 5000W peak pulse power with improved current ratings (42.1A and unspecified respectively), suitable for applications requiring enhanced transient suppression capability. These parts maintain voltage compatibility and active manufacturing status. Package variations (P600 vs. R-6) require board layout verification.

High-Power Alternative

The 15KP75A-TP (Micro Commercial Co) offers 15000W peak pulse power for demanding protection applications. This part maintains all voltage specifications and thermal operating range but requires confirmation of board space compatibility due to the R-6 package configuration.

All recommended substitutes maintain ROHS3 compliance and MSL 1 (Unlimited) moisture sensitivity rating, ensuring compatibility with standard manufacturing and storage environments.

Frequently Asked Questions (FAQ)

Q: Can I use a substitute part with higher power rating than the original 3KP75-B?

A: Yes. Higher power-rated parts (5KP75A series at 5000W or 15KP75A-TP at 15000W) are electrically compatible substitutes. The increased power capability provides additional design margin for transient suppression without affecting circuit operation. Verify board layout accommodates the physical package dimensions.

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

A: Both are through-hole axial packages for TVS diodes. P600 and R-6 differ in physical dimensions and lead spacing. Substitution between these packages requires verification that the printed circuit board layout accommodates the specific package geometry. Consult component datasheets for precise dimensional specifications.

Q: Are all substitute parts ROHS3 compliant?

A: Five of the six substitute parts carry explicit ROHS3 Compliant certification. The 3KP75A-TP does not specify RoHS status in the provided data. Confirm RoHS compliance requirements for your application before final part selection.

Q: Why does the 3KP75-B show as obsolete?

A: The 3KP75-B is no longer manufactured by Littelfuse Inc. Active equivalent parts from Littelfuse (5KP75A-B) and other manufacturers (Micro Commercial Co, Vishay) provide identical or superior electrical performance and are currently in production.

Q: Can I substitute based on voltage rating alone?

A: No. Voltage compatibility is necessary but not sufficient. Peak pulse current, power dissipation capability, and package type must also match application requirements. The 75V reverse standoff voltage is common across all substitutes, but clamping voltage and current handling vary. Select substitutes based on the complete parameter set defined in the Key Parameters section.

Q: What inventory status should I consider for production?

A: All substitute parts show active inventory levels ranging from 693 to 3900 pieces. The 5KP75A-E3/54 (Vishay) offers the highest inventory availability at 3900 pieces. Verify current stock levels with your component supplier before committing to production schedules.