Littelfuse 3KP70C Equivalent & Substitute Parts

Part Overview

The Littelfuse 3KP70C is a bidirectional Zener transient voltage suppressor (TVS) diode designed for general-purpose overvoltage protection applications. Featuring a 70V reverse standoff voltage and 3kW peak pulse power rating, this component provides transient suppression in through-hole P600 axial packaging. The 3KP70C is classified as obsolete, making identification of functionally equivalent active alternatives essential for ongoing design support and procurement continuity.

Substiute Parts

3KP70C

LittelfuseIn Stock: 9543KP70C Datasheet

Current PartRFQ

5KP70CA

Diotec SemiconductorIn Stock: 37915KP70CA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3KP70C is determined by strict equivalence across the following critical parameters:

Mandatory Matching Criteria:

• Reverse standoff voltage: 70V (nominal)
• Package type: P600 axial through-hole
• Bidirectional configuration: Single channel
• Device type: Zener TVS diode
• Application class: General-purpose transient suppression

Allowable Parameter Variance:

• Breakdown voltage (Min): Within ±10% of original specification
• Clamping voltage (Max): Within ±10% of original specification
• Peak pulse current: Equal to or greater than original rating
• Peak pulse power: Equal to or greater than original rating
• Operating temperature range: Must encompass or exceed original range

The Diotec Semiconductor 5KP70CA meets all mandatory matching criteria and demonstrates superior performance characteristics in peak pulse current and power ratings, making it a direct functional substitute.

Parameter Comparison

Engineering Selection Recommendations

The Diotec Semiconductor 5KP70CA is a qualified substitute for the obsolete Littelfuse 3KP70C based on the following engineering criteria:

Functional Equivalence: Both devices share identical reverse standoff voltage (70V), package configuration (P600 axial), and bidirectional Zener topology, ensuring direct mechanical and electrical compatibility in existing circuit designs.

Performance Enhancement: The 5KP70CA provides superior transient suppression capability with 44A peak pulse current and 5kW power rating compared to the 3KP70C specifications of 26.5A and 3kW, delivering enhanced protection margin without circuit modification.

Voltage Characteristics: Clamping voltage variance of -4.8% and breakdown voltage variance of +5.5% remain within acceptable engineering tolerance for general-purpose TVS applications, with the 5KP70CA demonstrating lower clamping voltage for improved transient suppression efficiency.

Product Status: The 5KP70CA maintains active production status with 3780 units in current inventory, ensuring long-term procurement availability and supply chain continuity.

Compliance: Both devices carry EAR99 ECCN classification. The 3KP70C is ROHS3 compliant; RoHS status for the 5KP70CA is not applicable per manufacturer specification.

Temperature Consideration: The 5KP70CA minimum operating temperature of -50°C is 5°C higher than the 3KP70C specification of -55°C. Applications requiring operation below -50°C require design review.

Frequently Asked Questions (FAQ)

Q: Can the 5KP70CA be used as a direct replacement for the 3KP70C without circuit modification?

A: Yes. Both devices feature identical 70V reverse standoff voltage, P600 axial through-hole package, and single-channel bidirectional Zener configuration. Direct substitution is mechanically and electrically compatible. The 5KP70CA's superior current and power ratings provide enhanced protection without requiring circuit redesign.

Q: What is the significance of the clamping voltage difference between the two parts?

A: The 5KP70CA exhibits 4.8% lower clamping voltage (113V vs. 118.65V) at peak pulse current. This represents improved transient suppression efficiency, as lower clamping voltage reduces voltage stress on protected circuitry during transient events. This difference is within acceptable engineering tolerance for general-purpose applications.

Q: Are there any temperature range limitations when substituting the 5KP70CA?

A: The 5KP70CA minimum operating temperature is -50°C, compared to -55°C for the 3KP70C. Applications requiring operation below -50°C must be evaluated for compatibility. Maximum operating temperature (175°C) is identical for both devices.

Q: How do the power ratings compare, and what does this mean for circuit protection?

A: The 5KP70CA provides 5kW peak pulse power versus 3kW for the 3KP70C, representing a 66.7% increase in transient energy dissipation capability. This enhanced rating provides greater protection margin against high-energy transient events without circuit modification.

Q: Is the P600 axial package identical between both devices?

A: Yes. Both the 3KP70C and 5KP70CA use P600 axial through-hole packaging, ensuring identical mechanical fit, lead spacing, and PCB mounting compatibility. No layout or assembly changes are required.

Q: What compliance certifications apply to each device?

A: Both devices carry EAR99 ECCN classification. The 3KP70C is ROHS3 compliant. The 5KP70CA RoHS status is not applicable per manufacturer specification. Applications subject to RoHS requirements should verify compliance with procurement specifications.