3KP43CA-B Equivalent & Substitute Parts

Part Overview

The 3KP43CA-B is a Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose voltage clamping applications. This bidirectional zener diode provides transient protection with a 43V reverse standoff voltage and 69.4V maximum clamping voltage. The part is classified as obsolete, making identification of suitable substitutes essential for ongoing design support and procurement continuity.

Substiute Parts

3KP43CA-B

Littelfuse Inc.In Stock: 8783KP43CA-B Datasheet

Current PartRFQ

5KP43CA-B

Littelfuse Inc.In Stock: 12125KP43CA-B Datasheet

DirectRFQ

3KP43CA-TP

Micro Commercial CoIn Stock: 9933KP43CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3KP43CA-B is determined by the following critical parameters:

• Voltage - Reverse Standoff: 43V (exact match required)
• Voltage - Clamping (Max) @ Ipp: 69.4V (exact match required)
• Current - Peak Pulse (10/1000µs): minimum 43.2A
• Operating Temperature Range: -55°C to 175°C minimum
• Mounting Type: Through Hole
• Package / Case: P600 or R-6 Axial compatible footprints
• Type: Zener, Bidirectional, single channel

Substitute parts must maintain identical voltage specifications while meeting or exceeding current and power ratings. Package compatibility is limited to axial through-hole configurations with equivalent mechanical dimensions.

Parameter Comparison

Engineering Selection Recommendations

5KP43CA-B is the primary substitute for the obsolete 3KP43CA-B. Both parts are manufactured by Littelfuse Inc. and maintain identical voltage specifications (43V standoff, 69.4V clamping). The 5KP43CA-B is currently in active production status with higher current capacity (74.6A versus 43.2A) and increased power dissipation (5000W versus 3000W), providing enhanced margin for transient protection. Both parts share the P600 axial package and are ROHS3 compliant with MSL 1 rating.

3KP43CA-TP is an alternative substitute manufactured by Micro Commercial Co. This part maintains identical electrical specifications to the original 3KP43CA-B (43.2A peak pulse current, 3000W power rating) and identical voltage parameters. The primary difference is the package designation (R-6 versus P600), which represents a mechanical variant of the axial through-hole configuration. This part is currently in active production status and ROHS3 compliant.

Selection between 5KP43CA-B and 3KP43CA-TP depends on application requirements: choose 5KP43CA-B for applications requiring higher transient current capacity or when Littelfuse continuity is preferred; choose 3KP43CA-TP when maintaining the original 3000W power rating and 43.2A specification is sufficient and package compatibility with R-6 footprint is acceptable.

Frequently Asked Questions (FAQ)

Q: Can the 5KP43CA-B be used as a direct replacement for the 3KP43CA-B?

A: Yes. Both parts maintain identical voltage specifications (43V standoff, 69.4V clamping) and operating temperature range. The 5KP43CA-B provides higher current capacity (74.6A) and power rating (5000W), making it suitable for applications originally designed for the 3KP43CA-B. The P600 axial package is identical between both parts.

Q: What is the difference between the 5KP43CA-B and 3KP43CA-TP?

A: The 5KP43CA-B and 3KP43CA-TP differ in current and power ratings. The 5KP43CA-B provides 74.6A peak pulse current and 5000W power dissipation, while the 3KP43CA-TP provides 43.2A and 3000W, matching the original 3KP43CA-B specification. The 3KP43CA-TP uses an R-6 axial package variant instead of P600. Both maintain identical voltage parameters.

Q: Are the P600 and R-6 packages mechanically compatible?

A: Both P600 and R-6 are axial through-hole package designations for TVS diodes. Mechanical compatibility depends on specific PCB footprint design. Verify that the lead diameter, lead spacing, and body dimensions of the R-6 package are acceptable for your application's through-hole mounting pattern before substitution.

Q: What compliance certifications apply to these substitute parts?

A: All three parts (3KP43CA-B, 5KP43CA-B, and 3KP43CA-TP) are ROHS3 compliant. The 3KP43CA-B and 5KP43CA-B carry MSL 1 (Unlimited) moisture sensitivity rating. All parts are classified under ECCN EAR99 and HTSUS 8541.10.0080.

Q: Why is the 3KP43CA-B marked as obsolete?

A: The 3KP43CA-B is classified as obsolete by Littelfuse Inc. The 5KP43CA-B is the active production equivalent from the same manufacturer, offering improved specifications and continued availability. For new designs or ongoing procurement, the 5KP43CA-B is the recommended path forward.