Littelfuse 3KP22 Transient Voltage Suppressor - Equivalent & Substitute Parts

Part Overview

The Littelfuse 3KP22 is a unidirectional transient voltage suppressor (TVS) diode designed for general-purpose overvoltage protection applications. It features a 22V reverse standoff voltage with a 37.28V maximum clamping voltage and 84.5A peak pulse current capability in a through-hole P600 axial package.

The 3KP22 is classified as obsolete. Identifying suitable substitute components is necessary to maintain design continuity and ensure continued availability for new production builds and field replacements.

Substiute Parts

3KP22

Littelfuse Inc.In Stock: 10053KP22 Datasheet

Current PartRFQ

5KP22A

Diotec SemiconductorIn Stock: 89065KP22A Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP22 is determined by the following critical parameters:

• Voltage Rating Match: Reverse standoff voltage must be 22V (±tolerance acceptable within standard TVS specifications)
• Package Compatibility: P600 axial through-hole package required for mechanical and electrical compatibility
• Unidirectional Configuration: Single-channel zener TVS diode topology
• Electrical Performance: Clamping voltage, peak pulse current, and power dissipation must meet or exceed the original specification to ensure equivalent or superior protection

The 5KP22A from Diotec Semiconductor meets all substitution criteria. It maintains the 22V standoff voltage and P600 package while providing enhanced electrical performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

The 5KP22A is a direct functional substitute for the obsolete 3KP22. Both components share identical voltage ratings, package geometry, and unidirectional topology. The 5KP22A is classified as active product status, ensuring continued availability and supply chain stability.

The 5KP22A demonstrates superior electrical performance with higher peak pulse current (141A vs. 84.5A) and greater power dissipation capability (5000W vs. 3000W), while maintaining a lower clamping voltage (35.5V vs. 37.28V). These characteristics provide enhanced transient protection margins in equivalent circuit applications.

The 5KP22A is ROHS3 compliant and carries EAR99 export classification, consistent with the original component's regulatory status.

Frequently Asked Questions (FAQ)

Q: Can the 5KP22A be used as a direct replacement for the 3KP22 in existing designs?

A: Yes. Both components maintain identical 22V reverse standoff voltage, P600 axial package configuration, and unidirectional zener topology. Pin-for-pin and footprint compatibility is assured. The 5KP22A's enhanced electrical performance provides equivalent or superior protection.

Q: What is the significance of the lower clamping voltage in the 5KP22A?

A: The 5KP22A's 35.5V maximum clamping voltage (versus 37.28V for the 3KP22) represents improved transient suppression efficiency. Lower clamping voltage reduces voltage stress on protected circuitry during transient events.

Q: Are there temperature range differences between these components?

A: The 3KP22 operates from -55°C to 175°C, while the 5KP22A operates from -50°C to 175°C. For applications requiring operation below -50°C, the original 3KP22 specification must be verified against actual system requirements.

Q: Why does the 5KP22A have higher peak pulse current and power ratings?

A: The 5KP22A is rated for 141A peak pulse current and 5000W power dissipation compared to the 3KP22's 84.5A and 3000W. These higher ratings reflect the component's enhanced capability to handle more severe transient events while maintaining voltage regulation within specified limits.

Q: Is the P600 package identical between both components?

A: Yes. Both the 3KP22 and 5KP22A use the P600 axial through-hole package. Mechanical dimensions, lead spacing, and mounting characteristics are identical, ensuring direct board-level compatibility.