SZ1SMB54AT3G Equivalent & Substitute Parts

Part Overview

The SZ1SMB54AT3G is a unidirectional transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for surface mount applications in the SMB package. This component provides transient voltage protection with a 54V reverse standoff voltage and 87.1V maximum clamping voltage at peak pulse current. The part is actively produced and carries automotive-grade qualification (AEC-Q101), making it suitable for demanding industrial and automotive applications requiring reliable overvoltage protection.

Substitute parts are identified when equivalent electrical performance and mechanical compatibility are maintained across the specified parameter range, ensuring direct interchangeability in circuit designs without performance degradation.

Substiute Parts

SZ1SMB54AT3G

Littelfuse Inc.In Stock: 1085SZ1SMB54AT3G Datasheet

Current PartRFQ

SMBJE54AH

Eaton - Electronics DivisionIn Stock: 3947SMBJE54AH Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SZ1SMB54AT3G is determined by strict equivalence across the following critical electrical and mechanical parameters:

Electrical Equivalence Criteria:

• Voltage - Reverse Standoff (Typ): 54V
• Voltage - Breakdown (Min): 60V
• Voltage - Clamping (Max) @ Ipp: 87.1V
• Current - Peak Pulse (10/1000µs): 6.9A
• Power - Peak Pulse: 600W
• Unidirectional topology (1 channel)

Mechanical Equivalence Criteria:

• Package / Case: DO-214AA, SMB
• Mounting Type: Surface Mount
• Tape & Reel (TR) packaging format

Compliance & Qualification:

• RoHS3 Compliant status
• AEC-Q101 automotive qualification
• Operating temperature range compatibility

Substitute parts must satisfy all electrical parameters within the specified tolerances and maintain identical mechanical packaging to ensure direct board-level interchangeability.

Parameter Comparison

Engineering Selection Recommendations

The SMBJE54AH (Eaton - Electronics Division) is a direct electrical and mechanical equivalent to the SZ1SMB54AT3G. Both components maintain identical voltage suppression characteristics, peak pulse current ratings, and power dissipation specifications. Both parts carry automotive-grade classification with AEC-Q101 qualification, ensuring compliance with automotive reliability standards.

The primary operational difference is the operating temperature range: the SZ1SMB54AT3G supports -65°C to 150°C, while the SMBJE54AH operates from -55°C to 150°C. Selection between these parts depends on the specific application's minimum operating temperature requirement. For applications requiring operation below -55°C, the SZ1SMB54AT3G is the appropriate choice. For applications within the -55°C to 150°C range, either part is suitable.

Both parts are actively produced, RoHS3 compliant, and available in Tape & Reel packaging for automated assembly. Inventory availability should be evaluated based on procurement lead times and supply chain requirements.

Frequently Asked Questions (FAQ)

Q: Can SMBJE54AH replace SZ1SMB54AT3G in all applications?

A: The SMBJE54AH is electrically and mechanically equivalent for applications operating within the -55°C to 150°C temperature range. Applications requiring operation below -55°C must use the SZ1SMB54AT3G due to its extended lower temperature limit of -65°C.

Q: Are the package dimensions identical between these parts?

A: Both parts use the DO-214AA (SMB) package with identical mechanical specifications, enabling direct board-level substitution without PCB layout modifications.

Q: Do both parts meet automotive qualification requirements?

A: Yes. Both the SZ1SMB54AT3G and SMBJE54AH carry AEC-Q101 automotive qualification and are RoHS3 compliant, meeting automotive industry reliability and environmental standards.

Q: What is the significance of the 54V reverse standoff voltage?

A: The 54V reverse standoff voltage indicates the maximum continuous voltage the diode can withstand without conducting. This parameter determines the circuit voltage level at which the TVS diode begins protection. Both substitute parts maintain this specification.

Q: Are there differences in capacitance specifications between these parts?

A: The SZ1SMB54AT3G specifies 330pF capacitance at 1MHz. The SMBJE54AH does not provide a capacitance specification in the available data. For applications where capacitance is a critical parameter, verify the SMBJE54AH specification with the manufacturer or confirm circuit tolerance to capacitance variation.

Q: Can these parts be used interchangeably in existing designs without re-qualification?

A: Both parts are automotive-grade with AEC-Q101 qualification. Substitution within the specified electrical and temperature parameters does not require design re-qualification. However, design documentation should be updated to reflect the part change.