5KP18A-B Transient Voltage Suppressor Equivalent & Substitute Parts

Part Overview

The 5KP18A-B is an active Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient protection applications. This unidirectional zener diode operates with an 18V reverse standoff voltage and provides 5000W peak pulse power dissipation through a P600 axial package. The component is ROHS3 compliant and maintains an unlimited moisture sensitivity level (MSL 1), making it suitable for standard industrial and commercial environments. Equivalent and substitute parts are identified based on matching electrical specifications and mechanical compatibility within the TVS diode category.

Substiute Parts

5KP18A-B

Littelfuse Inc.In Stock: 7205KP18A-B Datasheet

Current PartRFQ

5KP18A

Diotec SemiconductorIn Stock: 42185KP18A Datasheet

MFR RecommendedRFQ

5KP18A-TP

Micro Commercial CoIn Stock: 20485KP18A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 5KP18A-B are qualified based on the following critical electrical and mechanical parameters:

• Voltage - Reverse Standoff: 18V (exact match required)
• Voltage - Clamping (Max) @ Ipp: 29.2V (exact match required)
• Power - Peak Pulse: 5000W (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: P600 or R-6 Axial (compatible axial packages)
• Type: Zener, Unidirectional (exact match required)
• RoHS Status: ROHS3 Compliant (compliance requirement)

The 5KP18A (Diotec Semiconductor) and 5KP18A-TP (Micro Commercial Co) meet these substitution criteria with minor variations in peak pulse current (171A vs. 174.7A) and packaging format (Tape & Reel vs. Cut Tape), which do not affect functional equivalence for general-purpose transient protection applications.

Parameter Comparison

Engineering Selection Recommendations

All three parts maintain active product status and ROHS3 compliance, confirming their suitability for current design implementations. The 5KP18A (Diotec Semiconductor) provides direct electrical and mechanical equivalence with identical voltage ratings and power dissipation in the standard P600 axial package. The 5KP18A-TP (Micro Commercial Co) offers functional equivalence with compatible R-6 axial package geometry, though physical dimensions may differ slightly between P600 and R-6 packages.

Selection between these substitutes depends on packaging availability and PCB layout constraints. The Diotec 5KP18A maintains identical package specification (P600), while the Micro Commercial Co 5KP18A-TP requires verification of R-6 package compatibility with existing board designs. All three parts satisfy the electrical requirements for general-purpose transient voltage suppression applications.

Frequently Asked Questions (FAQ)

Q: Can the 5KP18A (Diotec) directly replace the 5KP18A-B (Littelfuse) in existing designs?

A: Yes. Both parts share identical voltage ratings (18V reverse standoff, 29.2V clamping), power dissipation (5000W), and P600 axial package specification. The minor difference in peak pulse current (171A vs. 174.7A) does not affect functional performance in general-purpose applications.

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

A: Both are axial through-hole packages formats for TVS diodes. P600 and R-6 represent different package designations with potentially different physical dimensions. Verification of PCB footprint compatibility is required before substituting 5KP18A-TP (R-6 package) for the original 5KP18A-B (P600 package).

Q: Are all three parts ROHS3 compliant?

A: Yes. The 5KP18A-B (Littelfuse), 5KP18A (Diotec), and 5KP18A-TP (Micro Commercial Co) are all ROHS3 compliant, meeting environmental and regulatory requirements for industrial and commercial applications.

Q: What is the operating temperature range difference between substitutes?

A: The 5KP18A-B and 5KP18A-TP operate across -55°C to 175°C, while the 5KP18A (Diotec) operates across -50°C to 175°C. For applications requiring operation below -50°C, the Littelfuse or Micro Commercial Co parts are required.

Q: Can peak pulse current variation affect circuit performance?

A: The 5KP18A (Diotec) specifies 171A peak pulse current compared to 174.7A for the 5KP18A-B. This 3.7A difference represents approximately 2% variation and does not impact functional equivalence for general-purpose transient protection where clamping voltage and power dissipation are the primary design criteria.