3KP85CA-B Equivalent & Substitute Parts

Part Overview

The 3KP85CA-B is a Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse, designed for general-purpose transient voltage protection applications. This component features an 85V reverse standoff voltage with a 137V maximum clamping voltage and 21.9A peak pulse current capability in a P600 axial through-hole package. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and procurement planning.

Substiute Parts

3KP85CA-B

LittelfuseIn Stock: 7783KP85CA-B Datasheet

Current PartRFQ

5KP85CA-B

Littelfuse Inc.In Stock: 7255KP85CA-B Datasheet

DirectRFQ

15KP85CA-TP

Micro Commercial CoIn Stock: 116815KP85CA-TP Datasheet

MFR RecommendedRFQ

3KP85CA-TP

Micro Commercial CoIn Stock: 10153KP85CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP85CA-B is determined by the following critical parameters:

• Voltage Rating Match: Reverse standoff voltage of 85V, breakdown voltage minimum of 94.4V, and clamping voltage maximum of 137V must be maintained
• Thermal Performance: Operating temperature range of -55°C to 175°C (TJ)
• Electrical Characteristics: Zener type, single bidirectional channel configuration
• Mechanical Compatibility: Through-hole mounting with axial package orientation
• Application Suitability: General-purpose transient voltage suppression

The identified substitute parts maintain these core electrical and mechanical parameters while differing in peak pulse current handling capability and power dissipation capacity. Package variations (P600 versus R-6) represent alternative axial through-hole configurations suitable for the same mounting methodology.

Parameter Comparison

Engineering Selection Recommendations

Direct Electrical Equivalent (Identical Power Rating): The 3KP85CA-TP from Micro Commercial Co provides identical electrical performance to the 3KP85CA-B, maintaining the same 21.9A peak pulse current and 3000W power dissipation. This part is currently active and ROHS3 compliant. The primary difference is the package configuration (R-6 versus P600), both of which are axial through-hole formats compatible with standard PCB mounting practices.

Higher Power Capability Alternatives: The 5KP85CA-B (Littelfuse) and 15KP85CA-TP (Micro Commercial Co) maintain identical voltage specifications while offering increased peak pulse current and power dissipation capacity. These parts are suitable for applications requiring enhanced transient suppression capability without voltage rating modification. Both are active products with current manufacturing support.

Compliance and Availability: All substitute parts maintain ROHS3 compliance and MSL Level 1 (unlimited moisture sensitivity), ensuring compatibility with modern manufacturing and storage requirements. The 5KP85CA-B and 15KP85CA-TP are actively manufactured, providing superior long-term availability compared to the obsolete 3KP85CA-B.

Frequently Asked Questions (FAQ)

Q: Can the 5KP85CA-B or 15KP85CA-TP be used as direct replacements for the 3KP85CA-B? A: Yes. All three parts maintain identical voltage ratings (85V reverse standoff, 137V clamping). The 5KP85CA-B and 15KP85CA-TP provide higher peak pulse current and power dissipation, making them suitable for the same applications and higher-stress environments. Electrical compatibility is confirmed across all voltage parameters.

Q: What is the difference between the P600 and R-6 packages? A: Both P600 and R-6 are axial through-hole package formats for TVS diodes. The primary distinction is physical size and lead configuration. Both are compatible with standard through-hole PCB assembly processes. Package selection should be verified against PCB footprint requirements and available board space.

Q: Is the 3KP85CA-TP an exact replacement for the 3KP85CA-B? A: The 3KP85CA-TP matches all electrical specifications of the 3KP85CA-B (21.9A peak pulse, 3000W power, 85V standoff voltage). The difference is the package format (R-6 versus P600). Both are axial through-hole configurations. Verify PCB footprint compatibility before substitution.

Q: Why are there multiple substitute options with different power ratings? A: The 3KP series (3kW), 5KP series (5kW), and 15KP series (15kW) represent a product family with identical voltage characteristics but different current-handling capabilities. Selection depends on the peak transient current expected in the application. Higher-rated parts provide design margin and are suitable for more demanding environments.

Q: Are all substitute parts RoHS compliant? A: Yes. All listed substitute parts are ROHS3 compliant with MSL Level 1 rating, meeting current environmental and manufacturing standards.