SMDJ85A-HR Transient Voltage Suppressor Diode - Equivalent & Substitute Parts

Part Overview

The SMDJ85A-HR is an 85V unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in surface-mount applications. The device features a 137V maximum clamping voltage, 21.9A peak pulse current capability, and 3000W peak pulse power dissipation in a DO-214AB (SMC) package. This part is active and in production with full RoHS3 compliance. Equivalent and substitute parts are identified based on matching electrical performance parameters and package compatibility to support design flexibility and supply chain continuity.

Substiute Parts

SMDJ85A-HR

Littelfuse Inc.In Stock: 1165SMDJ85A-HR Datasheet

Current PartRFQ

SMDJ85A

Alpha & Omega Semiconductor Inc.In Stock: 4587SMDJ85A Datasheet

DirectRFQ

SMCJ85A

MDDIn Stock: 17966SMCJ85A Datasheet

MFR RecommendedRFQ

SMCJ85A

MDDIn Stock: 17966SMCJ85A Datasheet

MFR RecommendedRFQ

SMCJ85A

MDDIn Stock: 17966SMCJ85A Datasheet

MFR RecommendedRFQ

SMCJ85A-13-F

Diodes IncorporatedIn Stock: 2706SMCJ85A-13-F Datasheet

MFR RecommendedRFQ

SMCJ85A-E3/57T

Vishay General Semiconductor - Diodes DivisionIn Stock: 1591SMCJ85A-E3/57T Datasheet

MFR RecommendedRFQ

SMCJ85A-TP

Micro Commercial CoIn Stock: 3417SMCJ85A-TP Datasheet

MFR RecommendedRFQ

SMLJ85A

Bourns Inc.In Stock: 9352SMLJ85A Datasheet

MFR RecommendedRFQ

SMLJ85A-TP

Micro Commercial CoIn Stock: 2264SMLJ85A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SMDJ85A-HR are grouped based on strict electrical and mechanical parameter matching. The primary substitution criteria are:

Critical Matching Parameters:

• Voltage - Reverse Standoff (Typ): 85V
• Voltage - Breakdown (Min): 94.4V
• Voltage - Clamping (Max) @ Ipp: 137V
• Package / Case: DO-214AB, SMC
• Mounting Type: Surface Mount
• Unidirectional Channels: 1
• Type: Zener

Secondary Consideration Parameters:

• Current - Peak Pulse (10/1000µs): 10.4A to 21.9A
• Power - Peak Pulse: 1500W to 3000W
• Operating Temperature Range: -55°C to 175°C minimum

All substitute parts maintain identical voltage specifications and package form factor. Variations in peak pulse current and power dissipation reflect different die sizes within the same package envelope. Parts are listed as direct substitutes when all critical parameters align; secondary parameters may vary within acceptable engineering tolerances for the application category.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts listed maintain full RoHS3 compliance and active product status. Selection between equivalent parts depends on application-specific requirements:

High Current Applications (≥20A Peak Pulse): SMDJ85A (Alpha & Omega Semiconductor Inc.), SMLJ85A (Bourns Inc.), and SMLJ85A-TP (Micro Commercial Co) provide 20.8A to 21.9A peak pulse current with 3000W power dissipation, matching the original SMDJ85A-HR specification.

Standard Current Applications (10-11A Peak Pulse): SMCJ85A (MDD), SMCJ85A-13-F (Diodes Incorporated), and SMCJ85A-E3/57T (Vishay General Semiconductor - Diodes Division) provide reduced peak pulse current at 1500W power dissipation, suitable for lower-energy transient protection requirements.

Extended Temperature Range: SMCJ85A-TP and SMLJ85A-TP extend the upper operating temperature to 175°C, compared to 150°C for most alternatives.

Lower Temperature Limit: SMDJ85A-HR maintains the lowest operating temperature at -65°C; SMDJ85A (Alpha & Omega) operates to -55°C minimum.

All parts are packaged in DO-214AB (SMC) surface-mount form factor with identical footprint compatibility. REACH compliance status varies; SMLJ85A (Bourns Inc.) is REACH Affected, while all other parts are REACH Unaffected.

Frequently Asked Questions (FAQ)

Q: Can SMCJ85A parts substitute for SMDJ85A-HR in all applications?

A: SMCJ85A variants are electrically equivalent in voltage specifications but provide reduced peak pulse current (10.4-11A versus 21.9A) and lower power dissipation (1500W versus 3000W). Substitution is valid only when the application transient energy does not exceed 1500W peak pulse power.

Q: What is the difference between SMCJ85A and SMLJ85A?

A: Both maintain identical voltage ratings and DO-214AB package form factor. SMLJ85A provides higher peak pulse current (20.8A) and 3000W power dissipation, compared to SMCJ85A at 11A and 1500W. Selection depends on transient energy requirements.

Q: Are all substitute parts pin-compatible with SMDJ85A-HR?

A: Yes. All listed parts use the DO-214AB (SMC) package with identical pin configuration and footprint, enabling direct PCB-level substitution without layout modification.

Q: Does operating temperature range affect substitution eligibility?

A: Operating temperature range is a secondary consideration parameter. SMDJ85A-HR operates -65°C to 150°C. Substitutes with narrower ranges (-55°C to 150°C or -50°C to 150°C) are acceptable if the application does not require the full -65°C lower limit. Extended-range parts (-55°C to 175°C) provide additional margin.

Q: What is the significance of the -TP suffix in part numbers?

A: The -TP suffix indicates Tape & Reel packaging format, consistent with the original SMDJ85A-HR. This designation confirms automated assembly compatibility and does not affect electrical performance.

Q: Is REACH compliance a critical substitution factor?

A: REACH compliance status is provided for regulatory documentation. SMLJ85A (Bourns Inc.) is REACH Affected; all other substitutes are REACH Unaffected. Selection depends on end-market regulatory requirements.

Q: Can SMDJ85A (Alpha & Omega) directly replace SMDJ85A-HR?

A: Yes, with one consideration: SMDJ85A operates to -55°C minimum, while SMDJ85A-HR extends to -65°C. If the application requires operation below -55°C, SMDJ85A-HR or equivalent parts with -65°C rating must be retained.