P4KE91-B Equivalent & Substitute Parts

Part Overview

The P4KE91-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features a 77.8V reverse standoff voltage with a 131.25V maximum clamping voltage and 3.3A peak pulse current capability in a through-hole DO-204AL (DO-41) axial package. The P4KE91-B is classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement continuity.

Substiute Parts

P4KE91-B

Littelfuse Inc.In Stock: 811P4KE91-B Datasheet

Current PartRFQ

P4KE91A

Taiwan Semiconductor CorporationIn Stock: 1147P4KE91A Datasheet

DirectRFQ

P4KE91A-B

LittelfuseIn Stock: 1179P4KE91A-B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the P4KE91-B are qualified based on the following electrical and mechanical parameters:

• Voltage - Reverse Standoff (Typ): 77.8V (exact match required)
• Voltage - Clamping (Max) @ Ipp: within acceptable range for circuit protection
• Current - Peak Pulse (10/1000µs): 3.3A (exact match required)
• Power - Peak Pulse: 400W (exact match required)
• Operating Temperature Range: -55°C to 175°C (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: DO-204AL, DO-41, Axial (exact match required)
• Type: Zener, Unidirectional (exact match required)

The substitute parts P4KE91A-B and P4KE91A meet these core electrical and mechanical criteria. Both maintain the same reverse standoff voltage, peak pulse current, power dissipation, temperature range, and physical package specifications. The primary difference is the clamping voltage specification, which is lower in the substitute parts (125V vs. 131.25V), representing a tighter voltage regulation characteristic suitable for the same application class.

Parameter Comparison

Engineering Selection Recommendations

Both P4KE91A-B and P4KE91A are active product alternatives to the obsolete P4KE91-B. Selection between these substitutes should be based on the following factors:

P4KE91A-B (Littelfuse, Bulk packaging) maintains manufacturer continuity with the original part, as both are manufactured by Littelfuse. This option is suitable for applications where maintaining the original manufacturer lineage is preferred for supply chain consistency.

P4KE91A (Taiwan Semiconductor Corporation, Tape & Reel packaging) offers an alternative from a different manufacturer with the same electrical specifications. The Tape & Reel packaging format is advantageous for automated assembly processes and higher-volume production environments.

Both substitute parts are ROHS3 compliant and carry MSL rating of 1 (Unlimited), matching the original part's environmental and regulatory compliance profile. The lower clamping voltage (125V vs. 131.25V) in both substitutes provides tighter voltage regulation, which is acceptable for general-purpose transient suppression applications within the same circuit protection class.

Frequently Asked Questions (FAQ)

Q: Can P4KE91A-B or P4KE91A be used as direct replacements for P4KE91-B?

A: Yes. Both substitute parts maintain identical reverse standoff voltage (77.8V), peak pulse current (3.3A), power dissipation (400W), operating temperature range (-55°C to 175°C), and physical package specifications (DO-204AL, DO-41, Axial through-hole). The clamping voltage difference (125V vs. 131.25V) represents a tighter regulation characteristic suitable for the same application class.

Q: What is the difference between P4KE91A-B and P4KE91A?

A: The primary differences are manufacturer and packaging format. P4KE91A-B is manufactured by Littelfuse in Bulk packaging, while P4KE91A is manufactured by Taiwan Semiconductor Corporation in Tape & Reel packaging. Both have identical electrical specifications and compliance ratings.

Q: Does the lower clamping voltage in the substitute parts affect circuit compatibility?

A: The substitute parts specify a maximum clamping voltage of 125V compared to 131.25V in the original part. This represents improved voltage regulation performance and is compatible with circuits designed for the P4KE91-B, as the lower clamping voltage provides enhanced transient suppression within the same protection class.

Q: Are the substitute parts RoHS compliant?

A: Yes. Both P4KE91A-B and P4KE91A are ROHS3 compliant, matching the compliance status of the original P4KE91-B.

Q: Which substitute part should be selected for automated assembly?

A: P4KE91A in Tape & Reel packaging is optimized for automated pick-and-place assembly processes. P4KE91A-B in Bulk packaging is suitable for manual assembly or lower-volume applications.