SMFE28ALH Transient Voltage Suppressor - Equivalent & Substitute Parts

Part Overview

The SMFE28ALH is an active Transient Voltage Suppressor (TVS) diode manufactured by Eaton - Electronics Division. This unidirectional zener diode is designed for transient overvoltage protection in surface mount applications, featuring a 28V reverse standoff voltage and 45.4V maximum clamping voltage. The device is packaged in SOD-123F format and qualifies for automotive applications under AEC-Q101 certification. Substitute parts are identified to provide equivalent electrical performance and mechanical compatibility for applications requiring component alternatives due to inventory constraints, supply chain considerations, or design flexibility.

Substiute Parts

SMFE28ALH

Eaton - Electronics DivisionIn Stock: 760SMFE28ALH Datasheet

Current PartRFQ

VTVS28ASMF-HM3-08

Vishay General Semiconductor - Diodes DivisionIn Stock: 30671VTVS28ASMF-HM3-08 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMFE28ALH is permissible with the VTVS28ASMF-HM3-08 based on the following electrical and mechanical equivalence criteria:

Voltage Parameters: Both devices maintain comparable reverse standoff voltages (28V vs. 27.9V) and breakdown voltages (31.1V vs. 31.4V), ensuring functionally equivalent overvoltage protection thresholds. The clamping voltage differential (45.4V vs. 47V) remains within acceptable tolerance for transient suppression applications.

Current Handling: Peak pulse current ratings are equivalent (8.8A vs. 8.21A), with both devices rated for 400W peak pulse power dissipation.

Thermal Performance: Both devices operate across the automotive temperature range (-55°C to 150°C minimum), with the substitute offering extended upper temperature capability (175°C).

Compliance & Certification: Both parts carry AEC-Q101 automotive qualification, ROHS3 compliance, and REACH unaffected status, meeting identical regulatory requirements.

Packaging & Mounting: Both devices are surface mount configurations with equivalent moisture sensitivity levels (MSL 1 - Unlimited).

Parameter Comparison

Engineering Selection Recommendations

Both the SMFE28ALH and VTVS28ASMF-HM3-08 are active products with equivalent automotive-grade certifications and regulatory compliance. Selection between these devices is determined by package footprint compatibility and thermal operating requirements.

The SMFE28ALH in SOD-123F package is suitable for applications with standard PCB layout constraints and operating temperatures up to 150°C. The VTVS28ASMF-HM3-08 in DO-219AB (SMF) package provides identical electrical performance with extended thermal capability to 175°C, making it appropriate for high-temperature automotive environments.

Both devices maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory alignment for automotive and industrial applications. AEC-Q101 qualification on both parts confirms suitability for automotive-grade transient protection circuits.

Frequently Asked Questions (FAQ)

Q: Can the VTVS28ASMF-HM3-08 directly replace the SMFE28ALH in existing designs?

A: Electrical substitution is valid based on equivalent voltage and current parameters. However, package geometry differs (SOD-123F vs. DO-219AB), requiring PCB layout verification to confirm footprint compatibility before implementation.

Q: What is the significance of the voltage parameter differences between these devices?

A: The reverse standoff voltage differential (28V vs. 27.9V) and clamping voltage differential (45.4V vs. 47V) are within normal manufacturing tolerances for TVS diodes. Both devices provide equivalent transient suppression performance for 28V nominal protection circuits.

Q: Are both devices suitable for automotive applications?

A: Yes. Both the SMFE28ALH and VTVS28ASMF-HM3-08 carry AEC-Q101 automotive qualification and are rated for automotive-grade operating temperatures. Both comply with ROHS3 and REACH regulatory requirements.

Q: What is the difference in peak pulse current ratings?

A: The SMFE28ALH is rated for 8.8A peak pulse current, while the VTVS28ASMF-HM3-08 is rated for 8.21A. Both devices dissipate 400W peak pulse power. The current differential reflects normal manufacturing variation between suppliers and does not affect functional equivalence for standard transient protection applications.

Q: Does the extended temperature range of the VTVS28ASMF-HM3-08 affect substitution decisions?

A: The VTVS28ASMF-HM3-08 operates to 175°C junction temperature, compared to 150°C for the SMFE28ALH. This extended range provides additional thermal margin in high-temperature environments but does not restrict substitution in applications operating within the SMFE28ALH temperature specification.

Q: What packaging considerations apply to these substitute parts?

A: The SMFE28ALH uses SOD-123F packaging, while the VTVS28ASMF-HM3-08 uses DO-219AB (SMF) packaging. Both are surface mount configurations with identical moisture sensitivity levels (MSL 1). PCB footprint and land pattern compatibility must be verified before design implementation.