P4KE18-B Equivalent & Substitute Parts

Part Overview

The P4KE18-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in through-hole applications. This component features a 15.3V reverse standoff voltage and 26.78V maximum clamping voltage with 400W peak pulse power handling capability in a DO-204AL (DO-41) axial package.

The P4KE18-B is classified as obsolete. Equivalent and substitute parts are necessary to maintain design continuity and ensure component availability for new production runs and field replacements.

Substiute Parts

P4KE18-B

Littelfuse Inc.In Stock: 829P4KE18-B Datasheet

Current PartRFQ

P4KE18A

Rectron USAIn Stock: 300122P4KE18A Datasheet

DirectRFQ

P4KE18A-B

Littelfuse Inc.In Stock: 929P4KE18A-B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the P4KE18-B are qualified based on the following electrical and mechanical parameters:

• Unidirectional TVS diode topology with single channel configuration
• Reverse standoff voltage within the P4KE series specification range
• Maximum clamping voltage compatible with circuit protection requirements
• Peak pulse current and power dissipation capacity of 400W
• Through-hole mounting in DO-204AL (DO-41) axial package
• Operating temperature range support from -55°C minimum
• ROHS3 compliance and general-purpose application classification

The following parts meet these substitution criteria:

P4KE18A (Rectron USA) - Active status, 18V reverse standoff, 25.2V clamping voltage P4KE18A-B (Littelfuse Inc.) - Active status, 15.3V reverse standoff, 25.5V clamping voltage

Parameter Comparison

Engineering Selection Recommendations

P4KE18A-B is the primary substitute for P4KE18-B. Both components are manufactured by Littelfuse Inc., share identical reverse standoff voltage (15.3V), peak pulse current (16.1A), and maximum operating temperature (175°C). The P4KE18A-B maintains active product status and ROHS3 compliance. Clamping voltage differential of 1.28V (26.78V vs. 25.5V) remains within acceptable protection margins for general-purpose applications.

P4KE18A (Rectron USA) is a secondary substitute option. This part maintains 400W power dissipation and compatible package configuration. The 18V reverse standoff voltage represents a 2.7V increase from the original specification. The maximum operating temperature is limited to 150°C, which is 25°C lower than the P4KE18-B. This part is suitable for applications where the elevated standoff voltage and reduced temperature range do not conflict with circuit requirements.

Both substitute parts carry active product status and full ROHS3 compliance, ensuring long-term availability and regulatory alignment.

Frequently Asked Questions (FAQ)

Q: Can P4KE18A replace P4KE18-B in all applications? A: P4KE18A is functionally compatible for general-purpose TVS protection. The 18V reverse standoff voltage is higher than the original 15.3V specification. Verify that your circuit design accommodates this voltage differential. The maximum operating temperature of 150°C is lower than P4KE18-B; confirm this meets your thermal requirements.

Q: What is the difference between P4KE18A and P4KE18A-B? A: P4KE18A is manufactured by Rectron USA with an 18V reverse standoff voltage and 150°C maximum operating temperature. P4KE18A-B is manufactured by Littelfuse Inc. with a 15.3V reverse standoff voltage and 175°C maximum operating temperature. P4KE18A-B provides closer electrical alignment to the original P4KE18-B specification.

Q: Are packaging differences between these parts significant? A: All three parts use DO-204AL (DO-41) axial through-hole packages. P4KE18-B and P4KE18A-B are supplied in their respective standard packages. P4KE18A is available in Tape & Reel format. Physical dimensions and pin configurations are identical, allowing direct board-level substitution.

Q: Do all substitute parts meet RoHS compliance? A: Yes. P4KE18A, P4KE18A-B, and the original P4KE18-B are all ROHS3 compliant with MSL rating of 1 (Unlimited), ensuring regulatory alignment and moisture handling consistency.

Q: Which substitute should I select for new designs? A: P4KE18A-B is recommended for new designs. It maintains the closest electrical specifications to P4KE18-B, including identical reverse standoff voltage and maximum operating temperature, while offering active product status and guaranteed long-term availability from Littelfuse Inc.