SMF18A-M3-18 Equivalent & Substitute Parts

Part Overview

The SMF18A-M3-18 is an 18V Transient Voltage Suppressor (TVS) diode manufactured by Vishay General Semiconductor - Diodes Division. This unidirectional Zener-type TVS diode is designed for general-purpose transient voltage suppression applications, featuring a 29.2V maximum clamping voltage and 6.8A peak pulse current capability in a surface-mount DO-219AB (SMF) package. The component is RoHS3 compliant and carries an unlimited moisture sensitivity level (MSL 1). Equivalent and substitute parts are identified to support procurement flexibility, inventory management, and design continuity.

Substiute Parts

SMF18A-M3-18

Vishay General Semiconductor - Diodes DivisionIn Stock: 823SMF18A-M3-18 Datasheet

Current PartRFQ

SMF18A-HM3-08

Vishay General Semiconductor - Diodes DivisionIn Stock: 27449SMF18A-HM3-08 Datasheet

DirectRFQ

SMF18A-TP

Micro Commercial CoIn Stock: 18663SMF18A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the SMF18A-M3-18 is determined by strict equivalence across the following electrical and mechanical parameters:

• Voltage - Reverse Standoff: 18V
• Voltage - Breakdown (Min): 20V
• Voltage - Clamping (Max) @ Ipp: 29.2V
• Current - Peak Pulse (10/1000µs): 6.8A
• Power - Peak Pulse: 200W
• Type: Zener, Unidirectional
• Mounting Type: Surface Mount
• RoHS Compliance: ROHS3

Two substitute parts meet these criteria:

SMF18A-HM3-08 (Vishay General Semiconductor - Diodes Division): Direct manufacturer equivalent with identical electrical specifications and DO-219AB packaging. Includes AEC-Q101 automotive qualification.

SMF18A-TP (Micro Commercial Co): Manufacturer-recommended equivalent with identical electrical specifications. Uses SOD-123FL packaging instead of DO-219AB, requiring PCB layout modification.

Parameter Comparison

Engineering Selection Recommendations

SMF18A-HM3-08 is the preferred direct substitute when package compatibility is maintained. This part is manufactured by Vishay and shares identical electrical specifications and DO-219AB packaging with the SMF18A-M3-18. The addition of AEC-Q101 automotive qualification provides enhanced reliability documentation for applications requiring automotive-grade components.

SMF18A-TP is a manufacturer-recommended equivalent suitable for applications where package transition from DO-219AB to SOD-123FL is acceptable. PCB layout and footprint modifications are required. This part is manufactured by Micro Commercial Co and maintains all critical electrical parameters.

Both substitute parts are active products with ROHS3 compliance and unlimited moisture sensitivity level (MSL 1), matching the compliance profile of the original part.

Frequently Asked Questions (FAQ)

Q: Can SMF18A-HM3-08 be used as a direct replacement for SMF18A-M3-18?

A: Yes. Both parts share identical electrical specifications (18V standoff, 29.2V clamping, 6.8A peak pulse current, 200W peak power) and the same DO-219AB package. No PCB modifications are required.

Q: What is the primary difference between SMF18A-TP and the original part?

A: The SMF18A-TP uses SOD-123FL packaging instead of DO-219AB. Electrical specifications are identical. PCB footprint and layout modifications are necessary for this substitution.

Q: Are all three parts RoHS compliant?

A: Yes. SMF18A-M3-18, SMF18A-HM3-08, and SMF18A-TP are all ROHS3 compliant.

Q: Does SMF18A-HM3-08 include automotive qualification?

A: Yes. SMF18A-HM3-08 carries AEC-Q101 automotive qualification. The original SMF18A-M3-18 does not specify this qualification.

Q: What is the moisture sensitivity level for all three parts?

A: All three parts have MSL 1 (Unlimited), indicating no moisture sensitivity restrictions.

Q: Can capacitance specifications differ between substitutes?

A: SMF18A-TP does not specify capacitance at 1MHz, while both SMF18A-M3-18 and SMF18A-HM3-08 specify 320pF. Verify capacitance requirements for your application before selecting SMF18A-TP.