1SMA70CAT3 Equivalent & Substitute Parts

Part Overview

The 1SMA70CAT3 is a transient voltage suppressor (TVS) diode manufactured by onsemi, designed for general-purpose overvoltage protection in surface-mount applications. This component features a 70V reverse standoff voltage with 113V maximum clamping voltage and 4.6A peak pulse current capability in a DO-214AC (SMA) package. The part is classified as obsolete, making equivalent substitutes necessary for new designs and ongoing production requirements.

Substiute Parts

1SMA70CAT3

onsemiIn Stock: 8751SMA70CAT3 Datasheet

Current PartRFQ

SMAJ70CA

MDDIn Stock: 1201SMAJ70CA Datasheet

DirectRFQ

SMAJ70CA

MDDIn Stock: 1201SMAJ70CA Datasheet

DirectRFQ

SMAJ70CA-TR

STMicroelectronicsIn Stock: 15221SMAJ70CA-TR Datasheet

DirectRFQ

SM4T82CAY

STMicroelectronicsIn Stock: 1105SM4T82CAY Datasheet

SimilarRFQ

SMA6J70CA-TR

STMicroelectronicsIn Stock: 5155SMA6J70CA-TR Datasheet

SimilarRFQ

SMAJ70CA-13-F

Diodes IncorporatedIn Stock: 75484SMAJ70CA-13-F Datasheet

SimilarRFQ

SMAJ70CA-TP

Micro Commercial CoIn Stock: 5940SMAJ70CA-TP Datasheet

SimilarRFQ

SMAJ70CAE3/TR13

Microchip TechnologyIn Stock: 776SMAJ70CAE3/TR13 Datasheet

SimilarRFQ

TV04A700JB-G

Comchip TechnologyIn Stock: 1130TV04A700JB-G Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1SMA70CAT3 is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - Reverse Standoff (Typ): 70V
• Voltage - Breakdown (Min): 77.8V
• Package / Case: DO-214AC, SMA
• Mounting Type: Surface Mount
• Bidirectional Channels: 1
• Type: Zener

Secondary Compatibility Parameters:

• Voltage - Clamping (Max) @ Ipp: 113V (direct match) or higher
• Current - Peak Pulse (10/1000µs): 4.6A (minimum requirement)
• Power - Peak Pulse: 400W (minimum requirement)
• Operating Temperature Range: Must encompass application requirements

Substitute parts are grouped into two categories:

Direct Electrical Equivalents (113V Clamping, 4.6A Peak Pulse): Parts matching all primary criteria with identical clamping voltage and peak pulse current specifications.

Functional Equivalents (Higher Performance): Parts with identical standoff and breakdown voltages but enhanced clamping voltage or peak pulse current ratings, suitable for applications requiring additional margin or higher transient energy absorption.

Parameter Comparison

Engineering Selection Recommendations

Direct Replacement (Identical Electrical Performance):

SMAJ70CA-13-F (Diodes Incorporated), SMAJ70CA-TP (Micro Commercial Co), TV04A700JB-G (Comchip Technology), and SMAJ70CA (MDD) provide direct electrical equivalence with 113V clamping voltage and 4.6A peak pulse current. All substitute options are ROHS3 compliant and carry active product status, addressing the obsolescence of the original 1SMA70CAT3. SMAJ70CAE3/TR13 (Microchip Technology) offers slightly enhanced performance with 4.4A peak pulse current and 500W power rating while maintaining the 113V clamping specification.

Enhanced Performance Alternatives:

SMAJ70CA-TR and SM4T82CAY (both STMicroelectronics) provide higher transient energy absorption with 146V clamping voltage and 16A peak pulse current, suitable for applications requiring additional overvoltage margin. SMA6J70CA-TR (STMicroelectronics) offers the highest performance tier with 120V clamping, 27A peak pulse current, and 600W power dissipation, with extended operating temperature range to 175°C.

Compliance Considerations:

All active substitute parts meet ROHS3 compliance requirements, whereas the original 1SMA70CAT3 is RoHS non-compliant. Selection should account for application-specific temperature requirements, with SMAJ70CA-TP and SMA6J70CA-TR supporting extended upper temperature limits to 175°C.

Frequently Asked Questions (FAQ)

Q: Can SMAJ70CA-TR or SM4T82CAY be used as direct replacements for 1SMA70CAT3?

A: These parts share identical standoff (70V) and breakdown (77.8V) voltages and the same DO-214AC package. However, they feature higher clamping voltage (146V vs. 113V) and significantly higher peak pulse current (16A vs. 4.6A). They are functionally compatible but provide enhanced protection margins. Circuit validation is necessary to confirm suitability for the specific application.

Q: What is the difference between SMAJ70CA-13-F and SMAJ70CA-TP?

A: Both parts provide identical electrical specifications (70V standoff, 113V clamping, 4.6A peak pulse) and DO-214AC packaging. The primary difference is operating temperature range: SMAJ70CA-13-F operates -55°C to 150°C (TJ), while SMAJ70CA-TP operates -55°C to 175°C (TA). Selection depends on application thermal requirements.

Q: Why does SMAJ70CAE3/TR13 show 4.4A peak pulse current instead of 4.6A?

A: SMAJ70CAE3/TR13 maintains the same 70V standoff and 113V clamping specifications but offers enhanced peak pulse current capability (4.4A vs. 4.6A) and higher power dissipation (500W vs. 400W). This provides additional transient energy handling capacity while maintaining the same voltage protection profile.

Q: Are all substitute parts available in the same packaging?

A: Yes, all substitute parts listed use DO-214AC (SMA) surface-mount packaging, ensuring mechanical and footprint compatibility with the original 1SMA70CAT3 design.

Q: What is the significance of RoHS3 compliance for these substitutes?

A: All active substitute parts are ROHS3 compliant, whereas the original 1SMA70CAT3 is RoHS non-compliant. This compliance status is critical for applications subject to environmental regulations and procurement requirements in regulated industries.

Q: Can SMA6J70CA-TR be used in applications designed for 1SMA70CAT3?

A: SMA6J70CA-TR shares the 70V standoff voltage and DO-214AC package but features significantly enhanced performance (120V clamping, 27A peak pulse, 600W power). It is functionally compatible and provides superior protection margins. Extended operating temperature range (-55°C to 175°C) may offer additional design flexibility.