SMF64AT1G Equivalent & Substitute Parts

Part Overview

The SMF64AT1G is a unidirectional transient voltage suppressor (TVS) diode manufactured by onsemi, designed for general-purpose overvoltage protection applications. This component features a 64V reverse standoff voltage with a 103V maximum clamping voltage and 1.7A peak pulse current capability in a surface-mount SOD-123FL package. The part is currently classified as obsolete, making identification of equivalent and substitute components essential for ongoing design support and procurement.

Substiute Parts

SMF64AT1G

onsemiIn Stock: 687SMF64AT1G Datasheet

Current PartRFQ

SMF64A

MeritekIn Stock: 20468SMF64A Datasheet

DirectRFQ

SMF48A

MeritekIn Stock: 22729SMF48A Datasheet

SimilarRFQ

SMF54A

Diotec SemiconductorIn Stock: 35342SMF54A Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SMF64AT1G are categorized based on electrical parameter compatibility within the TVS diode classification. The primary substitution criteria are:

Direct Electrical Equivalence: Parts maintaining identical or functionally equivalent reverse standoff voltage (64V), breakdown voltage (71.1V minimum), and clamping voltage (103V maximum) specifications, with peak pulse current ratings at or above 1.7A.

Similar Voltage Rating Substitutes: Parts with different reverse standoff voltages but compatible clamping characteristics for applications where the exact 64V standoff is not critical, provided the voltage protection window remains within acceptable system tolerances.

Package Compatibility: All substitute parts maintain the SOD-123FL surface-mount package format, ensuring mechanical and thermal compatibility with existing PCB layouts.

Thermal and Environmental Alignment: Operating temperature ranges spanning -55°C to 150°C or -50°C to 150°C, with moisture sensitivity levels of 1 (Unlimited) or Not Applicable, ensuring reliability across standard industrial and commercial environments.

Parameter Comparison

Engineering Selection Recommendations

SMF64A (Meritek) - Direct Equivalent

The SMF64A represents the primary direct substitute for the SMF64AT1G. This part maintains identical reverse standoff voltage (64V), breakdown voltage (71.1V), and clamping voltage (103V) specifications. The SMF64A offers a higher peak pulse current rating (1.94A versus 1.7A), providing enhanced transient protection margin. The part is currently in active production status with ROHS3 compliance and unlimited moisture sensitivity rating. Inventory availability is substantial at 20,400 units.

SMF48A (Meritek) - Lower Voltage Alternative

The SMF48A functions as a substitute for applications where a lower reverse standoff voltage (48V) is acceptable. This part provides a lower clamping voltage (77.4V) and higher peak pulse current (2.58A). Selection of this part requires verification that the system's maximum transient voltage does not exceed 77.4V. The SMF48A is active production status with ROHS3 compliance and unlimited moisture sensitivity rating.

SMF54A (Diotec Semiconductor) - Mid-Range Voltage Alternative

The SMF54A offers an intermediate voltage rating (54V reverse standoff, 87.1V clamping) with 2.3A peak pulse current. This part is suitable for applications where the 64V standoff voltage is not mandatory and system transient voltages remain below 87.1V. The SMF54A is in active production with ROHS3 compliance. Operating temperature range extends to -50°C minimum, which is acceptable for most industrial applications.

Frequently Asked Questions (FAQ)

Q: Can SMF64A be used as a direct replacement for SMF64AT1G?

A: Yes. The SMF64A maintains identical voltage specifications (64V standoff, 71.1V breakdown, 103V clamping) and package format (SOD-123FL). The higher peak pulse current rating (1.94A) provides additional protection margin. Both parts are unidirectional Zener TVS diodes with 200W peak pulse power rating.

Q: What is the difference between SMF64A and SMF48A?

A: The primary difference is the reverse standoff voltage: SMF64A operates at 64V while SMF48A operates at 48V. Consequently, SMF48A has a lower clamping voltage (77.4V versus 103V). SMF48A is suitable only for applications where transient voltages do not exceed 77.4V. Both parts share identical package format and 200W power rating.

Q: Can SMF54A replace SMF64AT1G in all applications?

A: SMF54A can replace SMF64AT1G only in applications where the system's maximum transient voltage does not exceed 87.1V. The 54V reverse standoff voltage and 87.1V clamping voltage are lower than the original part's 64V and 103V specifications. Verification of system voltage requirements is necessary before substitution.

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

A: All substitute parts are available in SOD-123F or SOD-123FL surface-mount packages, which are mechanically and thermally compatible. The package designation difference (SOD-123F versus SOD-123FL) does not affect PCB layout or thermal performance for this component category.

Q: What is the significance of the obsolete status of SMF64AT1G?

A: Obsolete status indicates that onsemi has discontinued manufacturing of this part. Active production alternatives (SMF64A, SMF48A, SMF54A) ensure long-term availability and supply chain continuity for new designs and ongoing production support.

Q: Do all substitute parts meet RoHS compliance?

A: SMF64A and SMF48A (Meritek) are ROHS3 compliant. SMF54A (Diotec) is ROHS3 compliant. All parts meet current environmental and regulatory requirements for electronic component manufacturing.