SMB6F48A Equivalent & Substitute Parts

Part Overview

The SMB6F48A 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 48V reverse standoff voltage with a 100V maximum clamping voltage and 40A peak pulse current capability in an SMBflat (DO-221AA) package.

The SMB6F48A is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications utilizing this TVS diode specification.

Substiute Parts

SMB6F48A

STMicroelectronicsIn Stock: 11132SMB6F48A Datasheet

Current PartRFQ

SMBJ48A-TR

STMicroelectronicsIn Stock: 1819SMBJ48A-TR Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMB6F48A is determined by matching the following critical electrical and mechanical parameters:

Voltage Parameters: Reverse standoff voltage (48V nominal), breakdown voltage minimum (53.2V), and clamping voltage maximum (100V) establish the protection threshold and response characteristics.

Current and Power Ratings: Peak pulse current (40A at 8/20µs) and peak pulse power (600W) define the transient energy handling capability.

Package and Mounting: Surface-mount configuration with SMB-family packaging ensures mechanical and thermal compatibility with existing PCB designs.

Device Type: Unidirectional zener-type TVS diode with single channel configuration.

The substitute part SMBJ48A-TR shares the same voltage class (48V reverse standoff) and power rating (600W peak pulse) as the SMB6F48A. However, the SMBJ48A-TR exhibits reduced peak pulse current capability (8.1A versus 40A) and operates within a narrower temperature range (-55°C to 150°C versus -55°C to 175°C). These differences must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

SMB6F48A Status: Obsolete. This part is no longer in active production. Existing inventory is available (11,024 pcs), but long-term supply cannot be guaranteed.

SMBJ48A-TR Status: Active. This part is in current production and represents the active equivalent within the STMicroelectronics TVS diode portfolio.

Compliance Considerations: Both parts carry identical regulatory classifications (REACH Unaffected, EAR99, HTSUS 8541.10.0080) and moisture sensitivity ratings (MSL 1). The SMBJ48A-TR includes RoHS3 compliance certification, whereas the SMB6F48A does not specify RoHS status.

Selection Basis: The SMBJ48A-TR is the recommended substitute for new designs and ongoing production where the reduced peak pulse current (8.1A) and narrower operating temperature range (-55°C to 150°C) are compatible with application requirements. For applications requiring the full 40A peak pulse current or operation above 150°C, alternative parts outside the provided substitute list must be evaluated.

Frequently Asked Questions (FAQ)

Q: Can the SMBJ48A-TR directly replace the SMB6F48A in existing designs?

A: Direct replacement is possible only if the application does not require peak pulse currents exceeding 8.1A and operates within the -55°C to 150°C temperature range. The SMBJ48A-TR provides equivalent voltage protection (48V standoff, 53.3V breakdown) and identical peak pulse power rating (600W). However, the reduced current capability and narrower temperature range must be verified against circuit requirements.

Q: What are the package differences between these parts?

A: The SMB6F48A uses SMBflat (DO-221AA) packaging with flat leads, while the SMBJ48A-TR uses standard SMB (DO-214AA) packaging. Both are surface-mount configurations, but PCB footprints differ. Layout modifications may be required during substitution.

Q: Why does the SMBJ48A-TR have a lower clamping voltage (77.4V) compared to the SMB6F48A (100V)?

A: Clamping voltage is determined by the device design and internal characteristics. Both parts maintain the same 48V reverse standoff voltage and 53V minimum breakdown voltage, ensuring equivalent protection thresholds. The lower clamping voltage of the SMBJ48A-TR reflects different internal construction and does not affect the voltage class or protection function for general-purpose applications.

Q: Are there temperature-related limitations when substituting the SMBJ48A-TR?

A: Yes. The SMB6F48A operates to 175°C junction temperature, while the SMBJ48A-TR is rated to 150°C. Applications requiring operation above 150°C cannot use the SMBJ48A-TR as a substitute.

Q: What is the significance of the current rating difference (40A versus 8.1A)?

A: Peak pulse current rating indicates the maximum transient current the device can suppress without damage. The SMB6F48A handles 40A pulses (8/20µs waveform), while the SMBJ48A-TR handles 8.1A. Applications with high-energy transients requiring 40A suppression capability cannot use the SMBJ48A-TR.

Q: Do both parts have the same regulatory compliance?

A: Both parts are REACH Unaffected and classified as EAR99 for export control purposes. The SMBJ48A-TR includes explicit RoHS3 compliance certification. For applications requiring RoHS compliance documentation, the SMBJ48A-TR is the appropriate choice.