3KP8.5C-B Equivalent & Substitute Parts

Part Overview

The 3KP8.5C-B is a Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose voltage protection applications. This through-hole component features an 8.5V reverse standoff voltage and 15.12V maximum clamping voltage with 208.3A peak pulse current capability. The product is currently obsolete, making identification of suitable substitute components essential for ongoing system maintenance and new design implementations where equivalent protection characteristics are required.

Substiute Parts

3KP8.5C-B

Littelfuse Inc.In Stock: 10453KP8.5C-B Datasheet

Current PartRFQ

5KP8.5CA-B

Littelfuse Inc.In Stock: 8405KP8.5CA-B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3KP8.5C-B is determined by the following critical electrical and mechanical parameters:

• Voltage - Reverse Standoff (Typ): Must be 8.5V to maintain circuit protection threshold compatibility
• Package / Case: Must be P600, Axial through-hole configuration for mechanical and electrical compatibility
• Mounting Type: Must be Through Hole to ensure PCB assembly compatibility
• Operating Temperature Range: Must support -55°C ~ 175°C (TJ) minimum
• RoHS Compliance: Must maintain ROHS3 Compliant status for regulatory alignment

The 5KP8.5CA-B qualifies as a direct substitute based on matching reverse standoff voltage (8.5V), identical package type (P600, Axial), through-hole mounting, and equivalent temperature operating range. While the 5KP8.5CA-B exhibits higher peak pulse current (354.2A vs. 208.3A) and greater peak pulse power (5000W vs. 3000W), these represent enhanced performance characteristics that do not compromise compatibility in applications designed for the 3KP8.5C-B.

Parameter Comparison

Engineering Selection Recommendations

The 5KP8.5CA-B is the qualified substitute for the obsolete 3KP8.5C-B. Selection is based on the following engineering criteria:

• Product Status Alignment: The 5KP8.5CA-B maintains Active product status, ensuring continued availability and manufacturer support, whereas the 3KP8.5C-B is obsolete.
• Regulatory Compliance: Both components maintain ROHS3 Compliant certification, satisfying environmental and regulatory requirements.
• Electrical Compatibility: Matching reverse standoff voltage (8.5V) and operating temperature range (-55°C ~ 175°C) ensure functional equivalence in circuit protection applications.
• Mechanical Compatibility: Identical P600 axial through-hole package enables direct PCB assembly compatibility without layout modifications.
• Performance Enhancement: The 5KP8.5CA-B provides superior peak pulse current (354.2A) and power dissipation (5000W) compared to the 3KP8.5C-B (208.3A, 3000W), offering enhanced transient protection capability without introducing compatibility issues.

Frequently Asked Questions (FAQ)

Q: Can the 5KP8.5CA-B be used as a direct replacement for the 3KP8.5C-B in existing designs?

A: Yes. Both components share identical reverse standoff voltage (8.5V), package type (P600, Axial), mounting configuration (Through Hole), and operating temperature range (-55°C ~ 175°C). The 5KP8.5CA-B can be substituted without circuit redesign or PCB layout modification.

Q: What are the key differences between the 3KP8.5C-B and 5KP8.5CA-B?

A: The primary differences are product status (obsolete vs. active), peak pulse current (208.3A vs. 354.2A), peak pulse power (3000W vs. 5000W), and clamping voltage (15.12V vs. 14.4V). The 5KP8.5CA-B provides enhanced transient suppression capability while maintaining electrical and mechanical compatibility.

Q: Are there any package or mounting considerations when substituting the 5KP8.5CA-B?

A: No. Both components use identical P600 axial through-hole packaging. No PCB modifications, lead bending adjustments, or assembly procedure changes are required.

Q: Does the 5KP8.5CA-B maintain the same regulatory compliance as the 3KP8.5C-B?

A: Yes. Both components are ROHS3 Compliant, satisfying equivalent environmental and regulatory requirements.

Q: Why is the 3KP8.5C-B obsolete?

A: The 3KP8.5C-B has been discontinued by Littelfuse Inc. The 5KP8.5CA-B represents the active equivalent in the manufacturer's current product portfolio, offering improved performance characteristics within the same package and electrical specification class.