Vishay General Semiconductor - Diodes Division SMF8V5A-M3-18

Overview

SMF8V5A-M3-18 from Vishay Semiconductors is a unidirectional surface-mount ESD protection diode in the SMF (DO-219AB) package, designed for low-capacitance transient voltage suppression in high-speed data lines. It features a 8.5 V stand-off voltage, 9.44–10.5 V reverse breakdown at 1 mA, 13.9 A peak pulse current (10/1000 μs), 14.4 V maximum clamping voltage at IPPM, and 674 pF typical junction capacitance at 0 V / 1 MHz.

For engineers reviewing the SMF8V5A-M3-18 datasheet, SMF8V5A-M3-18 pinout, SMF8V5A-M3-18 application, or SMF8V5A-M3-18 equivalent, this device is selected for robust ±30 kV IEC 61000-4-2 ESD protection in space-constrained USB, HDMI, and automotive infotainment interfaces where low clamping voltage and fast response are critical.

Technical Context

This diode operates as a unidirectional TVS (Transient Voltage Suppressor) with avalanche breakdown behavior, optimized for electrostatic discharge immunity in signal-line protection. Its low incremental surge resistance ensures minimal voltage overshoot during transient events, while its "Low Noise" technology enables sub-nanosecond response time to clamp ESD pulses before downstream IC damage occurs.

The SMF8V5A-M3-18 is rated for operation across –65 °C to +175 °C, qualified per AEC-Q101 for automotive use, and compatible with wave and reflow soldering per J-STD-020 MSL level 1 (peak 260 °C). It delivers 200 W peak pulse power (10/1000 μs) and 1000 W (8/20 μs), with thermal resistance R_thJA = 180 K/W on standard 3 mm × 3 mm Cu pads.

Key Specifications

Pinout & Package

SMF8V5A-M3-18 uses the DO-219AB (SOD-123W-compatible) surface-mount package with cathode-bar marking. The device has two terminals: anode and cathode. Cathode is marked by a bar on the top surface; orientation follows standard SOD-123W tape carrier direction with cathode toward sprocket holes.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ESD protection applications.

Compared with SMAJ8.5A-E3/5A and TPD4E001DPYR, the SMF8V5A-M3-18 offers optimal balance of automotive qualification, low clamping (14.4 V), moderate capacitance (674 pF), and compact DO-219AB size-making it ideal for cost-sensitive, space-constrained USB/HDMI protection in automotive and industrial systems where AEC-Q101 compliance is mandatory.

Availability

SMF8V5A-M3-18 is available at Aetrix Electronics and suitable for automotive infotainment, industrial sensor interfaces, and high-speed consumer connectivity applications requiring stable component supply and long-term lifecycle support.

Supply support for SMF8V5A-M3-18 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

Vishay Intertechnology is a global semiconductor manufacturer specializing in discrete components, sensors, and passive elements, with leadership in reliability-critical power and protection devices.

The SMF series targets high-reliability ESD protection in automotive and industrial environments, engineered to meet AEC-Q101 and IEC 61000-4-2 standards while delivering consistent clamping performance across extreme temperature ranges.

FAQ

What is the maximum clamping voltage of the SMF8V5A-M3-18 under a 10/1000 μs surge?

The SMF8V5A-M3-18 has a maximum clamping voltage (V_C) of 14.4 V when subjected to its rated peak pulse current of 13.9 A with a 10/1000 μs waveform. This value is measured per IEC 61000-4-5 test conditions and ensures downstream ICs experience limited overvoltage stress during transient events. The SMF8V5A-M3-18 maintains this clamping performance across its full operating temperature range of –65 °C to +175 °C.

Is the SMF8V5A-M3-18 qualified for automotive applications?

Yes, the SMF8V5A-M3-18 is AEC-Q101 qualified, confirming its suitability for automotive electronic systems including infotainment, body control, and sensor interfaces. It passes stress tests for temperature cycling, humidity, mechanical shock, and ESD per AEC-Q101 Rev D. The SMF8V5A-M3-18 is rated for continuous operation from –65 °C to +175 °C, supporting under-hood and cabin-mounted designs.

What is the junction capacitance of the SMF8V5A-M3-18 and how does it affect high-speed signals?

The SMF8V5A-M3-18 exhibits 674 pF typical junction capacitance at 0 V and 1 MHz. This value is low enough to preserve signal integrity on USB 2.0 (480 Mbps) and HDMI 1.4 (3.2 Gbps) channels without excessive rise-time degradation or insertion loss. The SMF8V5A-M3-18 achieves this while maintaining robust 200 W surge capability-unlike ultra-low-capacitance alternatives that sacrifice clamping performance.

Does the SMF8V5A-M3-18 have polarity markings, and how is it oriented on the PCB?

Yes, the SMF8V5A-M3-18 uses a cathode bar marking on the top surface of the DO-219AB package to indicate polarity. During placement, the cathode (bar side) must connect to ground or the reference node, while the anode connects to the protected signal line. Tape orientation follows standard SOD-123W carrier direction, with cathode aligned toward sprocket holes-ensuring correct automated pick-and-place registration. The SMF8V5A-M3-18 is unidirectional and will not protect reverse transients if installed backward.

What is the peak pulse power rating of the SMF8V5A-M3-18 for different surge waveforms?

The SMF8V5A-M3-18 delivers 200 W peak pulse power for the 10/1000 μs waveform (per IEC 61000-4-5 Annex A) and 1000 W for the 8/20 μs waveform. These ratings reflect its ability to absorb energy from common surge sources: the 10/1000 μs simulates lightning-induced surges on long traces, while the 8/20 μs represents high-current EFT/burst events. The SMF8V5A-M3-18 sustains these ratings with no derating up to +125 °C ambient temperature.