Vishay General Semiconductor - Diodes Division SMAJ13AHM3_A/H

Overview

SMAJ13AHM3_A/H from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMA (DO-214AC) package, designed for clamping voltage transients on power and signal lines. It features a 13 V standoff voltage (V_WM), 14.4–15.9 V breakdown voltage (V_BR) at 1 mA, 21.5 V maximum clamping voltage (V_C) at 18.6 A peak pulse current, and 400 W peak pulse power rating with 10/1000 μs waveform - used to protect MOSFETs, ICs, and sensor interfaces in automotive and industrial power rails.

For engineers reviewing the SMAJ13AHM3_A/H datasheet, SMAJ13AHM3_A/H pinout, SMAJ13AHM3_A/H application, or SMAJ13AHM3_A/H equivalent, this device is selected for robust ESD and surge protection where low-profile SMT placement, AEC-Q101 qualification, and stable clamping under repetitive transients are required.

Technical Context

This unidirectional TVS operates as a reverse-biased avalanche diode that remains non-conductive below V_WM = 13 V and clamps sharply above V_BR (min 14.4 V) to limit transient energy. Its glass-passivated junction ensures stable leakage (<1.0 μA at V_WM) and fast response time (<1.0 ps), enabling protection of sensitive CMOS inputs and low-voltage logic.

The device is rated for 40 A non-repetitive forward surge (IFSM), supports 150 °C max junction temperature, and meets MSL Level 1 per J-STD-020 with 260 °C reflow peak. Its halogen-free, RoHS-compliant HM3 suffix confirms compliance with automotive-grade material requirements and whisker resistance per JESD201 Class 2.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), surface-mount, single-axis molded case with cathode band marking. Matte tin-plated leads, solderable per J-STD-002 and JESD22-B102.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ13AHM3_A/H, SMAJ13AHE3_A/H offers identical clamping performance but omits halogen-free construction and AEC-Q101 validation, while SMAJ13A-E3/61 further removes automotive traceability and uses a different packaging format - making SMAJ13AHM3_A/H the only option meeting full automotive production requirements.

Availability

SMAJ13AHM3_A/H is available at Aetrix Electronics and suitable for automotive ECUs, industrial sensor modules, and telecom power supplies requiring stable component supply, AEC-Q101 compliance, and halogen-free materials.

Supply support for SMAJ13AHM3_A/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 applications where consistent clamping, low leakage, and AEC-Q101 validation are mandatory.

FAQ

What is the maximum clamping voltage of SMAJ13AHM3_A/H at its rated peak pulse current?

The SMAJ13AHM3_A/H has a maximum clamping voltage (V_C) of 21.5 V at its rated peak pulse current (I_PPM) of 18.6 A, measured with a 10/1000 μs waveform. This value is guaranteed across temperature and production lot, ensuring predictable overvoltage protection for downstream 24 V tolerant ICs. The SMAJ13AHM3_A/H maintains this clamping performance without degradation under repetitive surge conditions when properly mounted on recommended copper pads.

Is SMAJ13AHM3_A/H qualified for automotive applications?

Yes, SMAJ13AHM3_A/H is AEC-Q101 qualified, as confirmed by its HM3 suffix and Vishay's documentation. It undergoes stress testing for temperature cycling, humidity bias, mechanical shock, and high-temperature operating life - specifically validating suitability for automotive body electronics, infotainment, and power distribution modules. The SMAJ13AHM3_A/H meets these requirements without derating in ambient temperatures from −40 °C to +125 °C.

What does the "HM3" suffix indicate in SMAJ13AHM3_A/H?

The "HM3" suffix in SMAJ13AHM3_A/H denotes halogen-free, RoHS-compliant construction with AEC-Q101 qualification. It distinguishes the part from commercial-grade variants (e.g., E3) and confirms compliance with automotive material standards including JESD201 Class 2 whisker resistance and UL 94 V-0 flammability. The SMAJ13AHM3_A/H is supplied in 7" tape-and-reel (H code) and is traceable to Vishay's automotive production line.

How does SMAJ13AHM3_A/H differ from bidirectional TVS diodes like SMAJ13CA?

SMAJ13AHM3_A/H is unidirectional and intended for DC line protection with defined polarity (cathode band), whereas SMAJ13CA is bidirectional and symmetrical for AC or floating signal lines. The SMAJ13AHM3_A/H exhibits forward conduction behavior below V_F ≈ 3.5 V at 25 A, while SMAJ13CA clamps equally in both directions with no forward voltage drop specification. Use SMAJ13AHM3_A/H on positive-supply rails; use SMAJ13CA only where polarity reversal or AC coupling is present.

What PCB layout guidance applies to SMAJ13AHM3_A/H for optimal surge handling?

For optimal surge performance, SMAJ13AHM3_A/H must be mounted on minimum 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal, as specified in Vishay's datasheet. Short, wide traces to ground and protected line minimize inductance; avoid vias in current paths. Thermal relief is discouraged - solid copper connections maximize heat dissipation during repetitive 400 W pulses. The SMAJ13AHM3_A/H achieves rated P_PPM only when adhering to this pad layout.