3KP12 Transient Voltage Suppressor - Equivalent & Substitute Parts

Part Overview

The 3KP12 is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features a 12V reverse standoff voltage with a 20.9V maximum clamping voltage and 150.8A peak pulse current capability in a P600 axial through-hole package.

The 3KP12 is classified as obsolete. Identifying suitable substitute parts is necessary to maintain design continuity and ensure component availability for new production runs, repairs, and system upgrades.

Substiute Parts

3KP12

Littelfuse Inc.In Stock: 8113KP12 Datasheet

Current PartRFQ

5KP12A

Littelfuse Inc.In Stock: 45015KP12A Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3KP12 is determined by the following critical electrical and mechanical parameters:

Electrical Compatibility Criteria:

• Reverse standoff voltage: 12V (nominal)
• Unidirectional configuration: 1 channel
• Package type: P600 axial through-hole
• Operating temperature range: -55°C ~ 175°C (TJ)
• RoHS3 compliance requirement

Performance Considerations: Substitute parts must maintain the same reverse standoff voltage (12V) and unidirectional topology. Variations in clamping voltage, peak pulse current, and peak pulse power are acceptable provided the substitute meets or exceeds the original specifications for the intended protection circuit. The P600 axial package ensures mechanical and electrical compatibility with existing PCB layouts and component footprints.

The 5KP12A qualifies as a direct substitute based on matching reverse standoff voltage, unidirectional configuration, P600 package, operating temperature range, and RoHS3 compliance. The 5KP12A offers enhanced performance characteristics with higher peak pulse current (256.3A) and peak pulse power (5000W) compared to the 3KP12.

Parameter Comparison

Engineering Selection Recommendations

The 5KP12A is the qualified substitute for the 3KP12 based on the following engineering criteria:

Electrical Equivalence: Both parts maintain identical reverse standoff voltage (12V) and unidirectional topology, ensuring functional compatibility in existing circuit designs.

Package Compatibility: Both components use the P600 axial through-hole package, permitting direct mechanical substitution without PCB layout modifications.

Compliance Status: The 5KP12A holds active product status with ROHS3 compliance certification, ensuring long-term availability and regulatory alignment for new production and field replacements.

Performance Enhancement: The 5KP12A provides superior transient suppression capability with 256.3A peak pulse current and 5000W peak pulse power, compared to the 3KP12's 150.8A and 3000W specifications. This enhanced performance provides additional margin for overvoltage protection in the same physical package.

Temperature Rating: Both parts operate across the identical temperature range (-55°C ~ 175°C), maintaining thermal performance consistency.

Frequently Asked Questions (FAQ)

Q: Can the 5KP12A directly replace the 3KP12 in existing designs?

A: Yes. The 5KP12A is electrically and mechanically compatible with the 3KP12. Both components share the same 12V reverse standoff voltage, unidirectional configuration, P600 axial package, and operating temperature range. No circuit modifications or PCB layout changes are required.

Q: What is the primary difference between the 3KP12 and 5KP12A?

A: The primary differences are product status and performance specifications. The 3KP12 is obsolete, while the 5KP12A is active. The 5KP12A provides higher peak pulse current (256.3A vs. 150.8A) and peak pulse power (5000W vs. 3000W), offering enhanced transient suppression capability in the same package.

Q: Are there any package or mounting differences between these parts?

A: No. Both the 3KP12 and 5KP12A use the P600 axial through-hole package. They are mechanically identical and mount identically on PCBs.

Q: Does the 5KP12A meet the same compliance requirements as the 3KP12?

A: Yes. The 5KP12A is ROHS3 compliant and has a Moisture Sensitivity Level (MSL) of 1 (Unlimited), matching the compliance profile of the 3KP12.

Q: Why is the 3KP12 obsolete?

A: The 3KP12 has been discontinued by Littelfuse Inc. The 5KP12A represents the active product line continuation with equivalent electrical specifications and enhanced performance characteristics.