Taiwan Semiconductor Corporation SMF10A

Overview

SMF10A from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in SOD-123W package, rated for 200 W peak pulse power (10/1000 µs), 10 V working stand-off voltage (VWM), 17.0 V maximum clamping voltage (VC) at 11.8 A peak current, and junction temperature range of –55 °C to +175 °C. It protects automotive and industrial power rails against ESD and load-dump transients.

For engineers reviewing the SMF10A datasheet, SMF10A pinout, SMF10A application, or SMF10A equivalent, key selection criteria include clamping performance under ISO 7637-2 Pulse 1/2a/2b/3a/3b, low leakage (<5 µA @ 10 V), RoHS/halogen-free compliance, and SOD-123W thermal resistance (R_θJA = 100 °C/W).

Technical Context

The SMF10A operates as a unidirectional avalanche diode with a breakdown voltage range of 11.1–12.3 V at 1 mA test current. Its clamping action limits transient-induced overvoltage to ≤17.0 V at 11.8 A, enabling robust protection of downstream 12 V logic and microcontroller I/O pins.

Designed for high-reliability PCB mounting, it features glass-passivated junction, matte tin-plated leads compliant with J-STD-002, and meets JESD201 Class 2 whisker resistance. Moisture sensitivity level is J-STD-020 Level 1.

Key Specifications

Pinout & Package

Package: SOD-123W - Surface-mount plastic case with cathode band marking, UL 94V-0 molding compound, 0.016 g weight, and JESD201 Class 2 whisker resistance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with SMAJ10A and P6SMB10A, the SMF10A delivers optimal balance of compact SOD-123W size, low 5 µA leakage, and precise 17.0 V clamping-making it preferred for space-limited, low-power automotive and industrial sensors where consistent voltage limiting is critical.

Availability

SMF10A is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC inputs, LED lighting drivers, and smart meter power supplies requiring stable component supply across production lifecycles.

Supply support for SMF10A includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, serving automotive, industrial, and consumer markets since 1979.

The SMF10A belongs to TSC's SMF series of surface-mount TVS diodes, engineered specifically for ISO 7637-2-compliant transient suppression in 12 V/24 V systems with stringent space and thermal constraints.

FAQ

What is the maximum clamping voltage of the SMF10A under standard test conditions?

The SMF10A has a maximum clamping voltage (VC) of 17.0 V when subjected to a 10/1000 µs waveform at its peak pulse current of 11.8 A. This value is measured at TA = 25 °C and defines the upper voltage limit imposed on protected circuitry during transient events. The SMF10A maintains this clamping performance across its full operating temperature range, making it suitable for under-hood automotive applications where ambient temperatures exceed 100 °C.

Does the SMF10A meet automotive transient immunity standards?

Yes, the SMF10A meets ISO 7637-2 requirements for Pulses 1, 2a, 2b, 3a, and 3b-covering capacitive coupling, inductive load dump, and switching transients common in 12 V vehicle electrical systems. Its 200 W peak pulse power rating, low clamping voltage, and glass-passivated junction ensure reliable operation in automotive ECUs, body control modules, and lighting controllers. The SMF10A is not qualified to AEC-Q101, so system-level validation is required for automotive safety-critical functions.

What is the polarity configuration and marking convention for the SMF10A?

The SMF10A is a unidirectional TVS diode with cathode indicated by a visible band on the SOD-123W package body. The marking code "2W010" appears adjacent to the cathode band. During PCB layout, the cathode must be connected to the line being protected (e.g., 12 V rail), and the anode tied to ground. Reversing polarity will prevent clamping action and may cause device failure under reverse bias exceeding VWM.

How does the thermal performance of the SMF10A compare to larger-package TVS diodes?

The SMF10A has a junction-to-ambient thermal resistance (R_θJA) of 100 °C/W when mounted on a 5 mm × 5 mm copper pad, which is higher than SMA- or SMB-packaged alternatives (e.g., ~60 °C/W). This means the SMF10A heats up faster under repeated surges. For applications involving frequent transients, derating per Figure 2 in the datasheet is essential. The SMF10A remains optimal where board space is constrained and single-event surge protection dominates design requirements.

Is the SMF10A compatible with lead-free reflow soldering processes?

Yes, the SMF10A uses matte tin-plated leads compliant with J-STD-002 and supports standard lead-free reflow profiles (peak temperature ≤260 °C). Its moisture sensitivity level is J-STD-020 Level 1, meaning it can be stored indefinitely at ambient conditions without baking prior to assembly. The SOD-123W package also exhibits excellent coplanarity and solder joint reliability in automated placement and reflow processes used in high-volume automotive electronics manufacturing.