3KP45A Transient Voltage Suppressor - Equivalent & Substitute Parts

Part Overview

The 3KP45A is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse, designed for general-purpose overvoltage protection applications. This through-hole component features a 45V reverse standoff voltage with a 72.7V maximum clamping voltage and 41.3A peak pulse current capability. The product is currently obsolete, making identification of suitable substitute components essential for ongoing design support and procurement.

Substiute Parts

3KP45A

LittelfuseIn Stock: 10973KP45A Datasheet

Current PartRFQ

5KP45A

Littelfuse Inc.In Stock: 30585KP45A Datasheet

DirectRFQ

3KP45A-TP

Micro Commercial CoIn Stock: 11223KP45A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP45A is determined by the following critical parameters:

• Voltage - Reverse Standoff: 45V (exact match required)
• Voltage - Clamping (Max) @ Ipp: 72.7V (exact match required)
• Operating Temperature Range: -55°C to 175°C (exact match required)
• Mounting Type: Through Hole (exact match required)
• Type: Zener, Unidirectional (exact match required)
• Applications: General Purpose (exact match required)

Substitute parts must maintain identical electrical performance at the specified voltage and temperature parameters. Variations in peak pulse current and power dissipation are acceptable provided the substitute meets or exceeds the original specifications. Package variations within axial through-hole form factors are permissible when mechanical compatibility is confirmed.

Parameter Comparison

Engineering Selection Recommendations

5KP45A (Littelfuse Inc.) - Direct electrical equivalent with enhanced performance. This part maintains all critical voltage parameters identical to the 3KP45A while providing increased peak pulse current (70.2A) and power dissipation (5000W). Product status is Active with full ROHS3 compliance and REACH Unaffected designation. The identical P600 axial package ensures mechanical compatibility without modification.

3KP45A-TP (Micro Commercial Co) - Functional equivalent with package variation. This part matches all critical electrical specifications including voltage parameters, peak pulse current, and power dissipation. Product status is Active with ROHS3 compliance and REACH Unaffected designation. The R-6 axial package differs from the original P600 package; mechanical compatibility must be verified for the specific application circuit layout.

Frequently Asked Questions (FAQ)

Q: Can the 5KP45A replace the 3KP45A in all applications?

A: Yes. The 5KP45A maintains identical voltage specifications (45V standoff, 72.7V clamping) and operating temperature range. The increased peak pulse current (70.2A vs 41.3A) and power rating (5000W vs 3000W) provide enhanced performance margins. The identical P600 package ensures direct mechanical compatibility.

Q: What is the difference between the P600 and R-6 packages?

A: Both are axial through-hole packages for Zener diodes. The P600 and R-6 represent different physical form factors. Mechanical compatibility depends on PCB pad spacing and component clearance requirements in the specific circuit layout. Verify footprint dimensions before substitution.

Q: Is the 3KP45A-TP suitable for high-reliability applications?

A: The 3KP45A-TP meets ROHS3 compliance and REACH Unaffected requirements. However, product status is Active for Micro Commercial Co, whereas the original 3KP45A is Obsolete from Littelfuse. Compliance certifications are equivalent; design validation should confirm suitability for specific reliability requirements.

Q: Why is the original 3KP45A marked as Obsolete?

A: Littelfuse has discontinued the 3KP45A. The 5KP45A serves as the direct successor with identical electrical performance and enhanced power handling. For new designs or long-term procurement, the 5KP45A is the recommended active alternative.

Q: Can I use the 5KP45A in place of the 3KP45A-TP?

A: Yes. Both parts meet identical voltage and temperature specifications. The 5KP45A provides higher peak pulse current and power dissipation. Package compatibility (P600 vs R-6) must be verified for the specific PCB layout.