1SMB70AT3 Equivalent & Substitute Parts

Part Overview

The 1SMB70AT3 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 a 113V maximum clamping voltage and is packaged in the SMB/DO-214AA form factor. The part is currently classified as obsolete, making identification of active equivalent and substitute parts essential for ongoing design support and procurement.

Substiute Parts

1SMB70AT3

onsemiIn Stock: 43221SMB70AT3 Datasheet

Current PartRFQ

SMBJ70A

MDDIn Stock: 17296SMBJ70A Datasheet

DirectRFQ

SMBJ70A

MDDIn Stock: 17296SMBJ70A Datasheet

DirectRFQ

SMBJ70A-TR

STMicroelectronicsIn Stock: 12994SMBJ70A-TR Datasheet

DirectRFQ

PTVS64VP1UP,115

Nexperia USA Inc.In Stock: 4213PTVS64VP1UP,115 Datasheet

SimilarRFQ

SMBJ70A-TP

Micro Commercial CoIn Stock: 3838SMBJ70A-TP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the 1SMB70AT3 is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - Reverse Standoff (Typ): 70V
• Voltage - Clamping (Max) @ Ipp: 113V
• Current - Peak Pulse (10/1000µs): 5.3A to 5.8A
• Power - Peak Pulse: 600W
• Mounting Type: Surface Mount
• Package / Case: DO-214AA, SMB

Direct Equivalents maintain identical electrical specifications and packaging, enabling pin-for-pin replacement without circuit modification.

Similar Substitutes exhibit comparable voltage protection characteristics within acceptable engineering tolerances but may differ in package form factor (SOD-128 vs. SMB) or peak pulse current ratings. These require design review to confirm mechanical and thermal compatibility.

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalents (Recommended for Pin-for-Pin Replacement):

SMBJ70A (MDD), SMBJ70A-TR (STMicroelectronics), and SMBJ70A-TP (Micro Commercial Co) are functionally equivalent to the 1SMB70AT3. All three maintain the 70V reverse standoff voltage, 113V clamping voltage, and SMB/DO-214AA package form factor. These parts are currently in active production status with ROHS3 compliance, addressing the RoHS non-compliance limitation of the obsolete original part. Selection among these three should be based on packaging availability (Cut Tape, Digi-Reel, or Tape & Reel) and inventory requirements.

Similar Substitute (Design Review Required):

PTVS64VP1UP,115 (Nexperia) presents a similar substitute option with a lower reverse standoff voltage of 64V and clamping voltage of 103V. This part is qualified to AEC-Q101 automotive standards and is packaged in SOD-128 form factor rather than SMB. Use of this substitute requires verification that the lower voltage ratings remain within circuit protection requirements and that PCB layout can accommodate the different package geometry.

Frequently Asked Questions (FAQ)

Q: Can SMBJ70A (MDD) be used as a direct replacement for 1SMB70AT3?

A: Yes. SMBJ70A maintains identical voltage specifications (70V reverse standoff, 113V clamping) and SMB/DO-214AA packaging. The part is pin-compatible and requires no circuit modification. SMBJ70A is in active production with ROHS3 compliance.

Q: What is the difference between SMBJ70A-TR and SMBJ70A-TP?

A: Both are manufactured to the same electrical specifications. The difference is packaging format: SMBJ70A-TR is supplied in Cut Tape (CT) & Digi-Reel format by STMicroelectronics, while SMBJ70A-TP is supplied in Cut Tape format by Micro Commercial Co. Selection depends on procurement and assembly requirements.

Q: Why is PTVS64VP1UP,115 listed as a similar substitute rather than a direct equivalent?

A: PTVS64VP1UP,115 has a lower reverse standoff voltage (64V vs. 70V) and lower clamping voltage (103V vs. 113V). Additionally, it uses SOD-128 packaging instead of SMB/DO-214AA. These differences require circuit validation to confirm adequate protection margins and PCB layout compatibility.

Q: Are all substitute parts RoHS compliant?

A: Yes. SMBJ70A (MDD), SMBJ70A-TR (STMicroelectronics), SMBJ70A-TP (Micro Commercial Co), and PTVS64VP1UP,115 (Nexperia) are all ROHS3 compliant, addressing the RoHS non-compliance status of the obsolete 1SMB70AT3.

Q: What is the operating temperature range for each substitute?

A: SMBJ70A (MDD) operates from -50°C to 150°C (TJ). SMBJ70A-TR (STMicroelectronics) and PTVS64VP1UP,115 (Nexperia) operate from -55°C to 150°C. SMBJ70A-TP (Micro Commercial Co) has the widest range at -55°C to 175°C (TJ). Selection should match the thermal requirements of the target application.

Q: Do all parts have the same moisture sensitivity level?

A: Yes. All listed parts, including the original 1SMB70AT3, have MSL 1 (Unlimited), indicating no moisture sensitivity restrictions for storage or handling.