P6SMB440 Equivalent & Substitute Parts

Part Overview

The P6SMB440 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient voltage protection in surface-mount applications. This component features a 376V reverse standoff voltage and 600W peak pulse power rating in a DO-214AA (SMB) package. The part is currently listed as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Substiute Parts

P6SMB440

Littelfuse Inc.In Stock: 746P6SMB440 Datasheet

Current PartRFQ

P6SMB440A

Eaton - Electronics DivisionIn Stock: 20427P6SMB440A Datasheet

DirectRFQ

P6SMB440A

Eaton - Electronics DivisionIn Stock: 20427P6SMB440A Datasheet

DirectRFQ

SMBJ376A

Bourns Inc.In Stock: 774SMBJ376A Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the P6SMB440 is determined by strict alignment of electrical and mechanical parameters. The critical substitution criteria are:

• Reverse Standoff Voltage: 376V (Typ)
• Peak Pulse Power: 600W
• Peak Pulse Current: 1A (10/1000µs)
• Package Type: DO-214AA (SMB) surface mount
• Unidirectional Configuration: Single channel
• Operating Temperature Range: -55°C to 150°C (TJ)

Substitute parts must maintain these specifications within the allowed tolerances to ensure functional equivalence in circuit protection applications. Clamping voltage variations within the specified range do not preclude substitution, provided all other parameters remain within acceptable limits.

Parameter Comparison

Engineering Selection Recommendations

P6SMB440A (Eaton - Electronics Division): This substitute maintains all critical electrical parameters and package specifications. The part is in active production status with substantial inventory availability (20,400 pcs). However, this variant is RoHS non-compliant, which may restrict use in applications requiring RoHS3 compliance.

SMBJ376A (Bourns Inc.): This substitute provides full electrical and mechanical equivalence with the original P6SMB440. The part is in active production status with ROHS3 compliance certification, making it suitable for applications with RoHS requirements. Inventory availability is 717 pcs. This option is recommended for designs requiring regulatory compliance alignment with the original part's RoHS3 status.

Frequently Asked Questions (FAQ)

Q: Can P6SMB440A and SMBJ376A be used interchangeably with P6SMB440?

A: Both substitute parts maintain the critical electrical parameters (376V standoff, 600W peak power, 1A peak current) and identical package type (DO-214AA/SMB). They are mechanically and electrically interchangeable in circuit applications. Selection between them should be based on RoHS compliance requirements and supply chain availability.

Q: What is the significance of the clamping voltage difference between P6SMB440 (632.1V) and the substitutes (602V)?

A: Both values fall within acceptable operating ranges for TVS diode protection. The clamping voltage represents the maximum voltage at peak pulse current and does not prevent substitution. Circuit designers should verify that the lower clamping voltage of the substitute parts (602V vs. 632.1V) is acceptable for the specific transient protection application.

Q: Why is P6SMB440 listed as obsolete?

A: Littelfuse has discontinued this part number. Active substitutes from Eaton and Bourns provide equivalent functionality and are recommended for new designs and ongoing procurement.

Q: Does RoHS compliance status affect electrical performance?

A: RoHS compliance relates to material composition and environmental regulations, not electrical performance. Both RoHS-compliant (SMBJ376A) and non-compliant (P6SMB440A) substitutes deliver identical electrical specifications. Selection should be based on application regulatory requirements.

Q: Are there any package or mounting differences between these parts?

A: All three parts use the DO-214AA (SMB) surface-mount package with identical mechanical dimensions and land patterns. No PCB layout modifications are required when substituting between these parts.