Vishay General Semiconductor - Diodes Division SMAJ8.0AHM3/H

Overview

SMAJ8.0AHM3/H from Vishay General Semiconductor is a unidirectional transient voltage suppressor (TVS) diode in SMA (DO-214AC) package, designed for robust overvoltage protection of sensitive electronics. It features a 8.0 V stand-off voltage (V_WM), 8.89–9.83 V breakdown voltage (V_BR) at 10 mA, 13.6 V maximum clamping voltage (V_C) at 29.4 A peak pulse current, and 400 W peak pulse power rating with 10/1000 μs waveform - deployed on power rails and signal lines in automotive ECUs and industrial sensor interfaces.

For engineers reviewing the SMAJ8.0AHM3/H datasheet, SMAJ8.0AHM3/H pinout, SMAJ8.0AHM3/H application, or SMAJ8.0AHM3/H equivalent, key selection criteria include its AEC-Q101 qualification (HM3 suffix), halogen-free RoHS compliance, 150 °C max junction temperature, low incremental surge resistance, and verified clamping performance under repetitive transients per IEC 61000-4-5.

Technical Context

This TVS diode operates as a fast-acting shunt protector: when reverse voltage exceeds V_WM = 8.0 V, it avalanches into low-impedance conduction to clamp transient energy. Its glass-passivated junction ensures stable breakdown and low leakage (<50 μA at V_WM), while the SMA package supports automated SMT placement and meets MSL Level 1 (260 °C reflow peak).

The device delivers 400 W peak pulse power (derated to 300 W above 78 V), with thermal resistance R_θJA = 120 °C/W and R_θJL = 30 °C/W - enabling reliable operation on standard 0.2" × 0.2" copper pads without heatsinking in short-duration surge events.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), molded plastic case with matte tin-plated leads, compliant with J-STD-002 and JESD 22-B102 solderability standards. Polarity indicated by cathode band on unidirectional devices.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ8.0AHM3/H, SMAJ8.0A-M3/61 omits halogen-free and automotive qualification, while SMAJ8.0AHE3_A/H provides AEC-Q101 but lacks halogen-free compliance - making SMAJ8.0AHM3/H the sole option meeting both automotive reliability and green material mandates simultaneously.

Availability

SMAJ8.0AHM3/H is available at Aetrix Electronics and suitable for automotive electronic control units, industrial sensor modules, and telecom power supply designs requiring stable component supply with full AEC-Q101 and halogen-free compliance.

Supply support for SMAJ8.0AHM3/H 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 General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, MOSFETs, optoelectronics, and passive components with emphasis on reliability and application-specific performance.

The SMAJ series is engineered for high-energy transient suppression in harsh environments - targeting automotive, industrial, and telecom systems where robustness against ESD, EFT, and surge events is mission-critical.

FAQ

What is the clamping voltage of the SMAJ8.0AHM3/H under maximum rated surge current?

The SMAJ8.0AHM3/H has a maximum clamping voltage (V_C) of 13.6 V at its peak pulse current (I_PPM) of 29.4 A, measured with a 10/1000 μs waveform. This value is guaranteed per Vishay's datasheet (Document Number: 88390, Rev. 09-Jan-2024) and defines the upper voltage limit imposed on protected circuits during worst-case transient events. The SMAJ8.0AHM3/H maintains this clamping performance across its qualified operating temperature range.

Is SMAJ8.0AHM3/H qualified for automotive applications?

Yes, the SMAJ8.0AHM3/H is AEC-Q101 qualified, as confirmed by its HM3 suffix and documentation in Vishay's official datasheet. This qualification covers stress tests including high-temperature reverse bias (HTRB), temperature cycling, and ESD (HBM ≥ 8 kV). The SMAJ8.0AHM3/H is explicitly intended for automotive use cases such as body control modules, infotainment power supplies, and ADAS sensor interfaces where reliability under thermal and electrical stress is critical.

What does the "HM3" suffix indicate in SMAJ8.0AHM3/H?

The "HM3" suffix in SMAJ8.0AHM3/H denotes halogen-free, RoHS-compliant construction with AEC-Q101 qualification. Per Vishay's ordering information, "H" indicates AEC-Q101 qualification, "M3" specifies halogen-free and RoHS-compliant materials, and "/H" denotes 7-inch tape-and-reel packaging. This distinguishes SMAJ8.0AHM3/H from commercial-grade (E3/M3) or AEC-Q101-only (HE3) variants - confirming its suitability for green automotive programs like VW 80000 or GMW3172.

Can SMAJ8.0AHM3/H be used in bidirectional protection circuits?

No, SMAJ8.0AHM3/H is a unidirectional TVS diode, as indicated by its "A" suffix and cathode band marking. For bidirectional protection, the functionally matched part is SMAJ8.0CA (or SMAJ8.0CHM3/H for halogen-free AEC-Q101 version). Using SMAJ8.0AHM3/H in bidirectional configurations would result in forward conduction during negative transients, potentially damaging the device or failing to protect the circuit - always verify polarity alignment per application requirements.

What is the thermal resistance and maximum junction temperature of SMAJ8.0AHM3/H?

The SMAJ8.0AHM3/H has a typical junction-to-ambient thermal resistance (R_θJA) of 120 °C/W and junction-to-lead resistance (R_θJL) of 30 °C/W, measured on standard 0.2" × 0.2" copper pads. Its maximum operating junction temperature is +150 °C, enabling deployment in under-hood automotive environments and high-ambient industrial enclosures. These values are specified in the Thermal Characteristics table of Vishay's SMAJ5.0A–SMAJ188CA datasheet (88390).