SMB6F40A Equivalent & Substitute Parts

Part Overview

The SMB6F40A is a unidirectional transient voltage suppressor (TVS) diode manufactured by STMicroelectronics, designed for general-purpose overvoltage protection in surface-mount applications. This component features a 40V reverse standoff voltage with an 84V maximum clamping voltage and 48A peak pulse current capability in an SMBflat package configuration.

The SMB6F40A is classified as an obsolete product. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for systems utilizing this component.

Substiute Parts

SMB6F40A

STMicroelectronicsIn Stock: 10849SMB6F40A Datasheet

Current PartRFQ

SMBJ40A-TR

STMicroelectronicsIn Stock: 3286SMBJ40A-TR Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMB6F40A is determined by matching the following critical electrical parameters:

• Voltage - Reverse Standoff: 40V nominal
• Voltage - Breakdown (Min): 44.4V minimum
• Unidirectional Configuration: Single channel Zener diode
• Surface Mount Technology: Compatible with SMB-family packages
• Peak Pulse Power Handling: 600W capability

The SMBJ40A-TR meets the core voltage specifications (40V standoff, 44.4V breakdown minimum) and maintains the same 600W peak pulse power rating. Both components are manufactured by STMicroelectronics and operate within compatible temperature ranges. The primary distinction lies in package format and peak pulse current capability, which are application-dependent considerations.

Parameter Comparison

Engineering Selection Recommendations

The SMBJ40A-TR is an active-status substitute for the obsolete SMB6F40A. Both components share identical voltage specifications (40V standoff, 44.4V breakdown minimum) and equivalent peak pulse power ratings (600W), establishing electrical compatibility for general-purpose transient voltage suppression applications.

Key considerations for component selection:

Product Status: The SMBJ40A-TR maintains active manufacturing status with STMicroelectronics, ensuring long-term supply availability and design continuity compared to the obsolete SMB6F40A.

Compliance & Certifications: The SMBJ40A-TR is ROHS3 compliant, meeting current regulatory requirements. Both components carry REACH Unaffected status and EAR99 export classification.

Package Compatibility: The SMB6F40A uses DO-221AA SMBflat leads, while the SMBJ40A-TR uses DO-214AA SMB leads. Physical footprint differences require PCB layout verification before substitution.

Thermal Operating Range: The SMB6F40A operates to 175°C junction temperature, while the SMBJ40A-TR operates to 150°C. Applications requiring operation above 150°C require design review.

Peak Pulse Current: The SMB6F40A handles 48A peak pulse current versus 9.7A for the SMBJ40A-TR. High-current transient suppression applications must verify current capability requirements.

Frequently Asked Questions (FAQ)

Q: Can the SMBJ40A-TR directly replace the SMB6F40A in existing designs?

A: Electrical substitution is valid based on matching voltage specifications (40V standoff, 44.4V breakdown). Physical package differences (DO-221AA SMBflat versus DO-214AA SMB) require PCB footprint verification. Peak pulse current capability (48A versus 9.7A) must be evaluated against application transient current requirements.

Q: What are the key electrical parameters that determine substitution compatibility?

A: Reverse standoff voltage (40V), breakdown voltage minimum (44.4V), and peak pulse power rating (600W) are the primary electrical criteria. These parameters ensure the substitute component provides equivalent overvoltage protection characteristics in the circuit.

Q: Why does the SMBJ40A-TR have lower peak pulse current than the SMB6F40A?

A: Peak pulse current capability is determined by semiconductor die design and package thermal characteristics. The SMBJ40A-TR is rated for 9.7A peak pulse current, which is sufficient for many general-purpose applications. Applications requiring 48A peak pulse current must use components with equivalent current ratings.

Q: Are there temperature range differences between these components?

A: Yes. The SMB6F40A operates from -55°C to 175°C junction temperature, while the SMBJ40A-TR operates from -55°C to 150°C. Applications requiring operation above 150°C must use components with higher temperature ratings.

Q: What packaging format differences exist between these parts?

A: The SMB6F40A is supplied in Tape & Reel (TR) format in SMBflat package configuration. The SMBJ40A-TR is supplied in Cut Tape (CT) format in standard SMB package configuration. Packaging format affects handling, storage, and assembly processes but does not impact electrical performance.

Q: Is the SMBJ40A-TR compliant with current regulatory standards?

A: Yes. The SMBJ40A-TR is ROHS3 compliant and carries REACH Unaffected status, meeting current environmental and regulatory requirements. The obsolete SMB6F40A does not specify RoHS compliance status.