SMBJ78-E3/52 Equivalent & Substitute Parts

Part Overview

The SMBJ78-E3/52 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Vishay General Semiconductor - Diodes Division, designed for general-purpose overvoltage protection in surface-mount applications. This component features a 78V reverse standoff voltage, 139V maximum clamping voltage, and 4.3A peak pulse current capability in a DO-214AA (SMB) package. The part is currently listed as obsolete, making equivalent substitutes necessary for ongoing design support and procurement.

Substiute Parts

SMBJ78-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 1011SMBJ78-E3/52 Datasheet

Current PartRFQ

SMBJ78A-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 45116SMBJ78A-E3/52 Datasheet

DirectRFQ

SMBJ78E3/TR13

Microchip TechnologyIn Stock: 708SMBJ78E3/TR13 Datasheet

DirectRFQ

SMBJ78A

MDDIn Stock: 9439SMBJ78A Datasheet

MFR RecommendedRFQ

SMBJ78A

MDDIn Stock: 9439SMBJ78A Datasheet

MFR RecommendedRFQ

SMBJ78A

MDDIn Stock: 9439SMBJ78A Datasheet

MFR RecommendedRFQ

SMBJ78A-13-F

Diodes IncorporatedIn Stock: 8706SMBJ78A-13-F Datasheet

MFR RecommendedRFQ

SMBJ78A-TP

Micro Commercial CoIn Stock: 4182SMBJ78A-TP Datasheet

MFR RecommendedRFQ

SMBJ78AE3/TR13

Microchip TechnologyIn Stock: 1180SMBJ78AE3/TR13 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMBJ78-E3/52 is determined by the following critical electrical and mechanical parameters:

• Reverse Standoff Voltage (Typ): 78V — all substitutes maintain this specification
• Breakdown Voltage (Min): 86.7V — consistent across all alternatives
• Unidirectional Configuration: Single channel Zener diode topology
• Package / Case: DO-214AA (SMB) surface-mount form factor
• Mounting Type: Surface Mount
• RoHS Compliance: ROHS3 Compliant
• Moisture Sensitivity: MSL 1 (Unlimited)

Substitute parts are grouped into two categories based on clamping voltage performance:

Category A — Direct Electrical Match (139V Clamping): Parts maintaining the original 139V maximum clamping voltage specification, suitable for applications requiring identical transient suppression characteristics.

Category B — Functional Equivalent (126V Clamping): Parts with 126V maximum clamping voltage, representing a tighter clamping specification. These parts provide enhanced transient suppression performance while maintaining the same reverse standoff and breakdown voltage parameters.

Parameter Comparison

Engineering Selection Recommendations

Direct Replacement (Identical Electrical Performance):

SMBJ78E3/TR13 (Microchip Technology) is the primary direct replacement, maintaining the 139V clamping voltage specification of the original SMBJ78-E3/52. This part is currently in active production status with ROHS3 compliance and operates across -65°C to 150°C, providing extended low-temperature performance compared to the obsolete original.

Functional Equivalent (Enhanced Transient Suppression):

SMBJ78A-E3/52 (Vishay General Semiconductor - Diodes Division) provides a tighter clamping specification at 126V with increased peak pulse current capability (4.8A versus 4.3A). This part maintains Vishay manufacturing continuity and is actively produced with full ROHS3 compliance.

SMBJ78A-13-F (Diodes Incorporated), SMBJ78A-TP (Micro Commercial Co), SMBJ78AE3/TR13 (Microchip Technology), and SMBJ78A (MDD) all provide 126V clamping specifications with active product status and ROHS3 compliance. Selection among these alternatives depends on supply chain availability and preferred manufacturer qualification.

All substitute parts maintain the critical 78V reverse standoff voltage, 86.7V minimum breakdown voltage, DO-214AA package form factor, and MSL 1 rating required for functional compatibility with the original SMBJ78-E3/52 application.

Frequently Asked Questions (FAQ)

Q: Can SMBJ78A variants (126V clamping) be used in place of SMBJ78-E3/52 (139V clamping)?

A: Yes. The SMBJ78A variants provide a tighter clamping specification, meaning they suppress transient voltages to a lower maximum level (126V versus 139V). This represents enhanced protection performance. The critical parameters—reverse standoff voltage (78V), breakdown voltage (86.7V), and package form factor (DO-214AA)—remain identical, ensuring functional compatibility.

Q: What is the difference between SMBJ78E3/TR13 and SMBJ78AE3/TR13?

A: SMBJ78E3/TR13 maintains the original 139V clamping voltage with 4.3A peak pulse current. SMBJ78AE3/TR13 provides 126V clamping with 4.7A peak pulse current. Both are Microchip Technology products in active production with identical reverse standoff and breakdown voltages. Selection depends on whether the application requires the original clamping specification or can benefit from tighter transient suppression.

Q: Are all substitute parts available in the same DO-214AA package?

A: Yes. All listed substitute parts use the DO-214AA (SMB) surface-mount package, ensuring mechanical and electrical compatibility with the original SMBJ78-E3/52 footprint and PCB layout.

Q: Do all substitutes meet RoHS compliance requirements?

A: Yes. All substitute parts listed are ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity rating, matching the environmental and regulatory specifications of the original part.

Q: Which substitute offers the widest operating temperature range?

A: SMBJ78A-TP (Micro Commercial Co) operates across -55°C to 175°C, providing the widest temperature specification. SMBJ78E3/TR13 and SMBJ78AE3/TR13 (Microchip Technology) extend the low-temperature limit to -65°C, compared to the original -55°C specification.