SMCJ70 Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The SMCJ70 is a unidirectional Zener-type transient voltage suppressor diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in surface-mount applications. The device features a 70V reverse standoff voltage rating with a maximum clamping voltage of 118.65V at peak pulse current. The SMCJ70 is classified as obsolete; however, multiple active equivalent and substitute parts are available from alternative manufacturers that meet or exceed the electrical and mechanical specifications of the original component. Identifying suitable replacements is necessary to maintain design continuity and ensure supply chain availability.

Substiute Parts

SMCJ70

Littelfuse Inc.In Stock: 1080SMCJ70 Datasheet

Current PartRFQ

SMCJ70A

MeritekIn Stock: 4798SMCJ70A Datasheet

DirectRFQ

SMCJ70A

MeritekIn Stock: 4798SMCJ70A Datasheet

DirectRFQ

SMCJ70A-TP

Micro Commercial CoIn Stock: 6784SMCJ70A-TP Datasheet

MFR RecommendedRFQ

SMCJ70AE3/TR13

Microchip TechnologyIn Stock: 682SMCJ70AE3/TR13 Datasheet

MFR RecommendedRFQ

SMCJ70E3/TR13

Microchip TechnologyIn Stock: 926SMCJ70E3/TR13 Datasheet

MFR RecommendedRFQ

SMLJ70A

Bourns Inc.In Stock: 13902SMLJ70A Datasheet

MFR RecommendedRFQ

SMLJ70A-TP

Micro Commercial CoIn Stock: 751SMLJ70A-TP Datasheet

MFR RecommendedRFQ

SMLJ70AE3/TR13

Microchip TechnologyIn Stock: 1172SMLJ70AE3/TR13 Datasheet

MFR RecommendedRFQ

TV30C700J-G

Comchip TechnologyIn Stock: 1015TV30C700J-G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMCJ70 is determined by the following critical electrical and mechanical parameters:

• Voltage - Reverse Standoff: 70V (required match)
• Voltage - Clamping (Max) @ Ipp: 113V to 125V (acceptable range for SMCJ-series devices)
• Current - Peak Pulse (10/1000µs): 12A to 13.3A (SMCJ-series); 26.55A to 26.6A (SMLJ-series)
• Power - Peak Pulse: 1500W (SMCJ-series); 3000W (SMLJ-series)
• Package / Case: DO-214AB (SMC) (required match)
• Mounting Type: Surface Mount (required match)
• RoHS Status: ROHS3 Compliant (required match)
• Operating Temperature: -55°C to 150°C minimum (acceptable range)

Substitute parts are grouped into two categories: SMCJ-series devices (1500W power rating, 13.3A peak pulse current) and SMLJ-series devices (3000W power rating, 26.6A peak pulse current). Both categories maintain the same 70V reverse standoff voltage and DO-214AB package footprint, ensuring mechanical and electrical compatibility with the original SMCJ70 design.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts listed maintain the 70V reverse standoff voltage and DO-214AB (SMC) package footprint required for direct replacement of the SMCJ70. Selection between SMCJ-series and SMLJ-series devices depends on circuit power dissipation requirements:

SMCJ-series substitutes (SMCJ70A, SMCJ70A-TP, SMCJ70AE3/TR13, SMCJ70E3/TR13) are rated for 1500W peak pulse power and 12A to 13.3A peak pulse current, matching the original SMCJ70 electrical performance. These devices are suitable for applications where the original 1500W power rating is sufficient.

SMLJ-series substitutes (SMLJ70A, SMLJ70A-TP, SMLJ70AE3/TR13, TV30C700J-G) are rated for 3000W peak pulse power and 26.55A to 26.6A peak pulse current, providing enhanced transient suppression capability. These devices are suitable for applications requiring higher energy absorption or where circuit design margins necessitate increased power handling.

All substitute parts are ROHS3 compliant and carry MSL 1 (Unlimited) moisture sensitivity ratings. Devices from Micro Commercial Co (SMCJ70A-TP, SMLJ70A-TP) and Microchip Technology (SMCJ70AE3/TR13, SMCJ70E3/TR13, SMLJ70AE3/TR13) offer extended operating temperature ranges (-65°C to 150°C or -55°C to 175°C) compared to the original specification (-55°C to 150°C), providing additional design flexibility for temperature-critical applications.

Frequently Asked Questions (FAQ)

Q: Can SMLJ-series devices replace SMCJ-series devices in the same circuit?

A: SMLJ-series devices are mechanically and electrically compatible with SMCJ-series devices in the same DO-214AB package. The primary difference is increased power dissipation capability (3000W vs. 1500W) and peak pulse current (26.6A vs. 13.3A). SMLJ-series substitution is acceptable when circuit design permits the use of higher-rated components. No circuit modification is required.

Q: What is the difference between SMCJ70A and SMCJ70AE3/TR13?

A: Both devices share identical electrical specifications (70V reverse standoff, 113V clamping voltage, 13.3A peak pulse current, 1500W power rating) and DO-214AB package. The primary differences are manufacturer (Meritek vs. Microchip Technology), operating temperature range (SMCJ70AE3/TR13 extends to -65°C), and packaging format (Tape & Reel designation). Selection depends on supply chain availability and temperature requirements.

Q: Is the SMCJ70E3/TR13 a suitable replacement for the SMCJ70?

A: SMCJ70E3/TR13 maintains the 70V reverse standoff voltage, 1500W power rating, and DO-214AB package of the original SMCJ70. The clamping voltage is 125V (compared to 118.65V for SMCJ70) and peak pulse current is 12A (compared to 13.3A). This device is suitable for applications where the slightly higher clamping voltage and lower peak pulse current are acceptable within circuit design margins.

Q: Are all substitute parts ROHS3 compliant?

A: All substitute parts listed carry ROHS3 compliance certification. Moisture sensitivity level is MSL 1 (Unlimited) for all devices, indicating no special moisture control measures are required during storage or handling.

Q: What packaging formats are available for substitute parts?

A: Substitute parts are available in Tape & Reel (TR) format for automated assembly and Bulk format for manual assembly. Tape & Reel packaging is standard for high-volume production; Bulk packaging is available for lower-volume applications or component evaluation.