TPSMB68CA Equivalent & Substitute Parts

Part Overview

The TPSMB68CA is a transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for surface mount applications in the DO-214AA (SMB) package. This bidirectional zener diode operates with a reverse standoff voltage of 58.1V and provides voltage clamping at 92V maximum, with a peak pulse current rating of 6.6A. The device is classified as Active product status and carries automotive-grade qualification under AEC-Q101, making it suitable for high-reliability applications requiring transient overvoltage protection.

Substitute parts are identified based on matching or compatible electrical parameters including reverse standoff voltage, breakdown voltage, clamping voltage, peak pulse current, power dissipation, and operating temperature range, combined with equivalent surface mount packaging and compliance certifications.

Substiute Parts

TPSMB68CA

Littelfuse Inc.In Stock: 1246TPSMB68CA Datasheet

Current PartRFQ

P6SMB68CA

Eaton - Electronics DivisionIn Stock: 1480P6SMB68CA Datasheet

DirectRFQ

SZP6SMB68CAT3G

Littelfuse Inc.In Stock: 14436SZP6SMB68CAT3G Datasheet

MFR RecommendedRFQ

P6SMB68CA

Eaton - Electronics DivisionIn Stock: 1480P6SMB68CA Datasheet

DirectRFQ

SM6T68CAY

STMicroelectronicsIn Stock: 162885SM6T68CAY Datasheet

DirectRFQ

SMBJP6KE68CA-TP

Micro Commercial CoIn Stock: 4139SMBJP6KE68CA-TP Datasheet

DirectRFQ

P6SMB68CA-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 3138P6SMB68CA-E3/52 Datasheet

MFR RecommendedRFQ

SM6T68CA

STMicroelectronicsIn Stock: 31895SM6T68CA Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the TPSMB68CA are classified based on electrical parameter compatibility within the following criteria:

Primary Substitution Criteria:

• Reverse standoff voltage: 58.1V (±tolerance)
• Breakdown voltage minimum: 64.6V
• Clamping voltage maximum: 92V (±tolerance)
• Peak pulse current: 6.6A (±tolerance)
• Power dissipation: 600W
• Package type: DO-214AA / SMB surface mount
• Bidirectional channels: 1

Compliance and Certification Alignment:

• RoHS3 compliance required
• Automotive-grade preferred (AEC-Q101 qualification)
• Operating temperature range: minimum -55°C to 150°C

Substitute parts are grouped into two categories:

Group 1 - Direct Electrical Equivalents (Recommended): Parts matching all primary electrical parameters and automotive qualification: SZP6SMB68CAT3G, SMBJP6KE68CA-TP, P6SMB68CA-E3/52, SM6T68CA

Group 2 - Functional Equivalents (Parameter Variance): Parts with differing electrical characteristics but same package and application class: P6SMB68CA, SM6T68CAY

Parameter Comparison

Engineering Selection Recommendations

Tier 1 - Direct Substitutes (Preferred):

SZP6SMB68CAT3G (Littelfuse Inc.) and SMBJP6KE68CA-TP (Micro Commercial Co) provide direct electrical equivalence with matching reverse standoff voltage (58.1V), breakdown voltage (64.6V), and clamping voltage (92V). SZP6SMB68CAT3G maintains automotive-grade qualification and AEC-Q101 certification identical to the primary part. SMBJP6KE68CA-TP operates across an extended upper temperature limit to 175°C, matching the TPSMB68CA specification.

P6SMB68CA-E3/52 (Vishay General Semiconductor) and SM6T68CA (STMicroelectronics) are manufacturer-recommended alternatives. P6SMB68CA-E3/52 matches all electrical parameters with peak pulse current of 6.5A and maintains automotive-grade classification. SM6T68CA provides identical voltage specifications with higher peak pulse current capability (33A at 8/20µs pulse) and AEC-Q101 qualification.

Tier 2 - Functional Alternatives (Parameter Variance):

SM6T68CAY (STMicroelectronics) maintains the 58.1V reverse standoff and 64.6V breakdown voltage but exhibits higher clamping voltage (121V) and significantly higher peak pulse current (33A at 8/20µs). This part carries automotive-grade qualification and AEC-Q101 certification. Selection requires verification that the elevated clamping voltage is acceptable for the application circuit.

P6SMB68CA (Eaton - Electronics Division) exhibits substantial parameter deviation with reverse standoff voltage of 5.8V and clamping voltage of 10.5V, representing a different voltage class. This part is not electrically equivalent and should not be selected as a substitute for the TPSMB68CA without circuit redesign verification.

Compliance Considerations:

All substitute parts maintain ROHS3 compliance and Active product status. Parts designated as automotive-grade with AEC-Q101 qualification (SZP6SMB68CAT3G, SM6T68CA, SM6T68CAY) are preferred for applications requiring automotive reliability standards. General-purpose classified parts (SMBJP6KE68CA-TP, P6SMB68CA-E3/52, P6SMB68CA) are suitable for non-automotive applications where automotive qualification is not mandated.

Frequently Asked Questions (FAQ)

Q: What determines if a part can substitute for the TPSMB68CA?

A: Substitution is determined by matching electrical parameters: reverse standoff voltage (58.1V), breakdown voltage (64.6V minimum), clamping voltage (92V maximum), peak pulse current (6.6A nominal), and power dissipation (600W). The part must also be packaged in DO-214AA / SMB surface mount configuration with bidirectional single-channel topology. Compliance certifications and operating temperature range are secondary selection criteria.

Q: Can I use SM6T68CA or SM6T68CAY as substitutes despite higher clamping voltage?

A: SM6T68CA and SM6T68CAY exhibit clamping voltage of 121V compared to the TPSMB68CA specification of 92V maximum. Both parts maintain the same reverse standoff voltage (58.1V) and breakdown voltage (64.6V). Selection requires circuit analysis to confirm that the elevated clamping voltage does not exceed component or system voltage ratings. Both parts carry automotive-grade qualification and AEC-Q101 certification.

Q: What is the difference between the TPSMB68CA and P6SMB68CA?

A: These parts are not electrically equivalent. The TPSMB68CA operates at 58.1V reverse standoff with 92V clamping voltage, while P6SMB68CA operates at 5.8V reverse standoff with 10.5V clamping voltage. P6SMB68CA represents a different voltage class and is not a valid substitute without complete circuit redesign.

Q: Are all substitute parts automotive-qualified?

A: No. SZP6SMB68CAT3G, SM6T68CA, and SM6T68CAY carry automotive-grade classification with AEC-Q101 qualification. SMBJP6KE68CA-TP, P6SMB68CA-E3/52, and P6SMB68CA are classified as general-purpose parts without automotive qualification. Selection depends on application requirements and industry standards compliance.

Q: Do all substitute parts support the same operating temperature range?

A: No. The TPSMB68CA operates from -65°C to 175°C. SZP6SMB68CAT3G and P6SMB68CA-E3/52 operate to -65°C minimum but only to 150°C maximum. SMBJP6KE68CA-TP extends to 175°C upper limit but operates from -55°C minimum. SM6T68CA and SM6T68CAY operate from -55°C to 150°C. Application thermal requirements must be verified against selected substitute part specifications.

Q: Is packaging identical across all substitute parts?

A: All substitute parts use DO-214AA / SMB surface mount packaging with identical footprint and land pattern compatibility. Packaging designation may vary by manufacturer (SMB, SMBJ, or DO-214AA nomenclature), but physical dimensions and PCB mounting characteristics are equivalent.

Q: What is the significance of RoHS3 compliance versus RoHS compliance?

A: ROHS3 Compliant indicates full compliance with the current Restriction of Hazardous Substances Directive including all restricted substance categories. RoHS Compliant (without the "3" designation) may indicate compliance with earlier directive versions. For new designs, ROHS3 compliance is the current standard requirement.