TPSMB68A Equivalent & Substitute Parts

Part Overview

The TPSMB68A is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for surface mount applications in the DO-214AA (SMB) package. This component operates with a reverse standoff voltage of 58.1V, a clamping voltage of 92V at peak pulse current, and a peak pulse power rating of 600W. The part is AEC-Q101 qualified for automotive applications and maintains active product status with 3,453 units in current inventory.

Equivalent and substitute parts are necessary when the primary part becomes unavailable, when supply chain optimization is required, or when design flexibility across multiple manufacturers is needed while maintaining electrical and mechanical compatibility within specified parameters.

Substiute Parts

TPSMB68A

Littelfuse Inc.In Stock: 3541TPSMB68A Datasheet

Current PartRFQ

P6SMB68A

Eaton - Electronics DivisionIn Stock: 32269P6SMB68A Datasheet

MFR RecommendedRFQ

SM6T68AY

STMicroelectronicsIn Stock: 980SM6T68AY Datasheet

DirectRFQ

SMBJP6KE68A-TP

Micro Commercial CoIn Stock: 5551SMBJP6KE68A-TP Datasheet

DirectRFQ

P6SMB68A

Eaton - Electronics DivisionIn Stock: 32269P6SMB68A Datasheet

MFR RecommendedRFQ

P6SMB68A-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 6338P6SMB68A-E3/52 Datasheet

MFR RecommendedRFQ

P6SMB68A-E3/5B

Vishay General Semiconductor - Diodes DivisionIn Stock: 3885P6SMB68A-E3/5B Datasheet

MFR RecommendedRFQ

SM6T68A

STMicroelectronicsIn Stock: 125258SM6T68A Datasheet

MFR RecommendedRFQ

SM6T68A-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 30411SM6T68A-E3/52 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TPSMB68A is determined by strict equivalence across the following critical parameters:

Voltage Parameters: Reverse standoff voltage (58.1V typical), breakdown voltage minimum (64.6V), and clamping voltage maximum at peak pulse current (92V) must remain within specification to ensure proper transient suppression without affecting circuit operation.

Current and Power Ratings: Peak pulse current (10/1000µs pulse shape) and peak pulse power (600W) define the transient energy handling capability. Substitute parts must maintain these ratings to provide equivalent protection.

Package and Mounting: All substitute parts must use the DO-214AA (SMB) surface mount package to ensure mechanical and electrical compatibility with existing PCB layouts and assembly processes.

Electrical Type: All substitutes are unidirectional Zener TVS diodes with a single channel configuration.

Compliance and Certifications: RoHS3 compliance and automotive-grade qualification (AEC-Q101) are maintained across all substitute options to support regulated applications.

Substitute parts are grouped into two categories: direct electrical equivalents with identical voltage and current specifications, and manufacturer-recommended alternatives that meet the same functional requirements within the specified parameter ranges.

Parameter Comparison

Engineering Selection Recommendations

Direct Electrical Equivalents (Identical Voltage and Current Specifications):

P6SMB68A-E3/52 and P6SMB68A-E3/5B from Vishay General Semiconductor are direct substitutes with matching 58.1V reverse standoff, 92V clamping voltage, and 6.5A peak pulse current. Both maintain 600W peak pulse power and ROHS3 compliance. Operating temperature range is -65°C to 150°C, which covers the primary operating window of the TPSMB68A. These parts are suitable for general purpose applications.

SMBJP6KE68A-TP from Micro Commercial Co provides identical electrical specifications (58.1V standoff, 92V clamping, 6.6A peak pulse current) with extended upper operating temperature to 175°C, matching the TPSMB68A thermal range. This part is qualified for general purpose applications and maintains ROHS3 compliance.

Alternative Electrical Specifications (Higher Clamping Voltage and Current):

SM6T68A and SM6T68AY from STMicroelectronics feature higher clamping voltage (121V) and significantly higher peak pulse current (33A at 8/20µs pulse shape). These parts maintain the same 58.1V reverse standoff voltage and 600W peak pulse power. Both are AEC-Q101 qualified for automotive applications and ROHS3 compliant. Operating temperature range is -55°C to 150°C. These parts are suitable when higher transient energy absorption is required within the same voltage class.

SM6T68A-E3/52 from Vishay General Semiconductor offers the same electrical characteristics as the STMicroelectronics SM6T68A series (121V clamping, 33A peak pulse current) with identical thermal and compliance ratings, providing an alternative source within the higher-performance category.

Selection Criteria:

For direct replacement in existing designs with no circuit modifications, select P6SMB68A-E3/52, P6SMB68A-E3/5B, or SMBJP6KE68A-TP. The SMBJP6KE68A-TP is preferred when the full -65°C to 175°C operating range of the TPSMB68A must be maintained.

For applications requiring enhanced transient suppression capability, select SM6T68A, SM6T68AY, or SM6T68A-E3/52. These parts provide higher clamping voltage and current handling while maintaining the same voltage class and power rating.

For automotive applications requiring AEC-Q101 qualification, select TPSMB68A (primary), SM6T68A, or SM6T68AY.

Frequently Asked Questions (FAQ)

Q: Can P6SMB68A-E3/52 be used as a direct replacement for TPSMB68A?

A: Yes. Both parts share identical reverse standoff voltage (58.1V), breakdown voltage (64.6V minimum), and clamping voltage (92V). Peak pulse current is 6.5A versus 6.6A on the TPSMB68A, which is within acceptable tolerance for the same 600W power rating. Both use DO-214AA (SMB) surface mount packages. Operating temperature range is -65°C to 150°C on the P6SMB68A-E3/52 versus -65°C to 175°C on the TPSMB68A; verify that your application does not require operation above 150°C.

Q: What is the difference between SM6T68A and TPSMB68A?

A: Both parts maintain the same 58.1V reverse standoff voltage and 600W peak pulse power. The SM6T68A features higher clamping voltage (121V versus 92V) and significantly higher peak pulse current (33A at 8/20µs pulse shape versus 6.6A at 10/1000µs on the TPSMB68A). This makes the SM6T68A suitable for applications requiring greater transient energy absorption. Operating temperature range on SM6T68A is -55°C to 150°C. Both are ROHS3 compliant; SM6T68A is AEC-Q101 qualified.

Q: Are all substitute parts in the same package?

A: All substitute parts use the DO-214AA surface mount package, commonly designated as SMB or SMBJ. This ensures mechanical compatibility with existing PCB layouts. Verify your assembly process specifications for any package variant requirements (SMB versus SMBJ designation).

Q: Which substitute part has the widest operating temperature range?

A: SMBJP6KE68A-TP from Micro Commercial Co maintains the full -65°C to 175°C operating temperature range of the TPSMB68A. All other substitutes have upper temperature limits of 150°C or 175°C; verify your application thermal requirements before selection.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All substitute parts listed maintain ROHS3 compliance, matching the environmental qualification of the TPSMB68A.

Q: Which substitute parts are AEC-Q101 qualified for automotive applications?

A: TPSMB68A (primary part), SM6T68A, and SM6T68AY are AEC-Q101 qualified. If automotive qualification is required, select from these three options. Other substitutes are suitable for general purpose applications.