5KP18C-B Transient Voltage Suppressor Diode - Equivalent & Substitute Parts

Part Overview

The 5KP18C-B is a bidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features an 18V reverse standoff voltage rating and 5000W peak pulse power handling capability in a through-hole P600 axial package. The product is currently obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for continued system support and new designs.

Substiute Parts

5KP18C-B

Littelfuse Inc.In Stock: 11855KP18C-B Datasheet

Current PartRFQ

5KP18CA

Diotec SemiconductorIn Stock: 61755KP18CA Datasheet

DirectRFQ

5KP18CA-B

Littelfuse Inc.In Stock: 7835KP18CA-B Datasheet

DirectRFQ

SLD18-018-B

Littelfuse Inc.In Stock: 1065SLD18-018-B Datasheet

MFR RecommendedRFQ

15KP18CA-TP

Micro Commercial CoIn Stock: 129215KP18CA-TP Datasheet

MFR RecommendedRFQ

5KP18CA-TP

Micro Commercial CoIn Stock: 16475KP18CA-TP Datasheet

MFR RecommendedRFQ

5KP18CE3/TR13

Microchip TechnologyIn Stock: 9465KP18CE3/TR13 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 5KP18C-B is determined by the following critical parameters:

• Voltage - Reverse Standoff (Typ): Must be 18V
• Bidirectional Channels: Must be 1
• Mounting Type: Must be Through Hole
• Power - Peak Pulse: Must be 5000W (5kW) or greater
• Operating Temperature Range: Must encompass -55°C to 175°C
• RoHS Status: Must be ROHS3 Compliant
• Type: Must be Zener

All identified substitute parts meet these core electrical and mechanical requirements. Variations in voltage clamping characteristics, package case designations (P600 vs. R-6), and packaging formats (Bulk, Tape & Reel, Cut Tape) are permissible within the substitution scope, as these do not affect functional compatibility in the application circuit.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Identical Package P600)

The 5KP18CA-B (Littelfuse Inc., Active status) and SLD18-018-B (Littelfuse Inc., Active status, AEC-Q101 qualified) provide direct mechanical and electrical compatibility with the obsolete 5KP18C-B. Both maintain the P600 axial package format and support the full -55°C to 175°C operating temperature range. The SLD18-018-B variant includes automotive-grade qualification (AEC-Q101), suitable for applications requiring automotive compliance.

Alternative Package Substitutes (R-6 Package)

The 5KP18CA-TP (Micro Commercial Co, Active status) and 15KP18CA-TP (Micro Commercial Co, Active status) utilize the R-6 axial package instead of P600. These components maintain electrical compatibility but require mechanical board layout verification due to package case differences. The 15KP18CA-TP provides enhanced power handling at 15000W peak pulse, offering design margin for high-stress applications.

Extended Voltage Clamping Option

The 5KP18CE3/TR13 (Microchip Technology, Active status) offers the highest voltage clamping characteristic at 32.2V maximum, providing additional transient suppression margin while maintaining 5000W power rating and P600 package compatibility.

Cross-Manufacturer Alternative

The 5KP18CA (Diotec Semiconductor, Active status) provides equivalent electrical performance in P600 package but operates within a reduced temperature range (-50°C to 175°C). This variant is suitable for applications not requiring the full -55°C lower temperature limit.

Frequently Asked Questions (FAQ)

Q: Can I use the 15KP18CA-TP as a direct replacement for the 5KP18C-B?

A: The 15KP18CA-TP meets all core electrical requirements (18V standoff, 1 bidirectional channel, through-hole mounting, ROHS3 compliance) and exceeds power handling specifications at 15000W. However, it uses an R-6 axial package instead of P600, requiring verification that board layout and component spacing accommodate the different package dimensions.

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

A: Both are through-hole axial packages for TVS diodes. P600 and R-6 differ in physical dimensions and lead spacing. Component selection must verify that the selected package fits the existing PCB footprint and lead hole spacing.

Q: Is the 5KP18CA from Diotec Semiconductor fully compatible?

A: The 5KP18CA meets electrical substitution criteria but operates at -50°C minimum temperature versus the original -55°C specification. For applications requiring operation below -50°C, this variant is not suitable. For standard industrial temperature ranges, it provides equivalent performance.

Q: Why does the SLD18-018-B cost more than other substitutes?

A: The SLD18-018-B includes AEC-Q101 automotive qualification and is designated as automotive-grade. This certification adds manufacturing and testing requirements. Selection of this variant is necessary only for automotive or safety-critical applications requiring AEC-Q101 compliance.

Q: Can I substitute a higher power-rated device like 15KP18CA-TP in a design rated for 5000W?

A: Yes. Higher power ratings provide design margin and do not create compatibility issues. The 15KP18CA-TP at 15000W will function correctly in circuits designed for 5000W devices. Verify that the R-6 package dimensions are compatible with your PCB layout.

Q: Are all substitutes ROHS3 compliant?

A: Yes. All identified substitute parts carry ROHS3 Compliant status, matching the original 5KP18C-B specification.