Vishay General Semiconductor - Diodes Division SMCJ75AHM3_A/H

Overview

SMCJ75AHM3_A/H from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMC (DO-214AB) package, designed for high-energy surge protection with 75 V standoff voltage, 121 V clamping voltage at 12.4 A peak pulse current, and 1500 W peak pulse power rating. It protects MOSFETs, ICs, and sensor signal lines against inductive switching transients and lightning-induced surges in automotive and industrial power systems.

For engineers reviewing the SMCJ75AHM3_A/H datasheet, SMCJ75AHM3_A/H pinout, SMCJ75AHM3_A/H application, or SMCJ75AHM3_A/H equivalent, key selection criteria include unidirectional polarity, AEC-Q101 qualification, halogen-free RoHS compliance, and thermal resistance of 75 °C/W junction-to-ambient under standard pad layout.

Technical Context

This TVS diode operates as a clamping device that remains non-conductive below 75 V reverse standoff voltage (VWM), then rapidly transitions to low-impedance conduction above its 83.3–92.1 V breakdown range (VBR) to limit transient voltages. Its glass-passivated junction ensures stable leakage performance and fast response time under 10/1000 μs surge waveforms.

Designed for automated SMT assembly, it meets MSL level 1 per J-STD-020 with 260 °C lead-free reflow peak temperature tolerance and supports bidirectional variants via CA suffix (e.g., SMCJ75CA), though SMCJ75AHM3_A/H is strictly unidirectional with cathode band marking.

Key Specifications

Pinout & Package

Package: SMC (DO-214AB), surface-mount, molded plastic case with matte tin-plated leads solderable per J-STD-002 and JESD 22-B102; 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 SMCJ75AHM3_A/H, SMAJ75AHE3_A/H offers reduced surge capacity in a smaller footprint, while SMCJ75AHE3_A/H provides identical protection performance without halogen-free or automotive-grade assurance-enabling trade-offs between compliance, reliability, and cost.

Availability

SMCJ75AHM3_A/H is available at Aetrix Electronics and suitable for automotive power distribution, industrial sensor interface protection, telecom power supply input, and consumer appliance motor drive applications requiring stable component supply and long-term lifecycle support.

Supply support for SMCJ75AHM3_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 designs and manufactures discrete semiconductors including diodes, rectifiers, and TVS devices, with emphasis on high-reliability, high-performance components for demanding environments.

The SMCJ series targets high-energy transient suppression in automotive, industrial, and telecom infrastructure, where robust clamping, AEC-Q101 qualification, and consistent thermal performance are essential design requirements.

FAQ

What is the clamping voltage of SMCJ75AHM3_A/H at its rated peak pulse current?

The SMCJ75AHM3_A/H has a maximum clamping voltage (VC) of 121 V when subjected to its rated peak pulse current (IPPM) of 12.4 A under a 10/1000 μs waveform. This value is measured per JEDEC standards and defines the upper voltage limit imposed on protected circuitry during surge events. The SMCJ75AHM3_A/H maintains this clamping performance across its specified operating temperature range.

Is SMCJ75AHM3_A/H qualified for automotive applications?

Yes, SMCJ75AHM3_A/H is AEC-Q101 qualified, confirming its suitability for automotive electronic systems. The HM3 suffix denotes halogen-free, RoHS-compliant construction combined with AEC-Q101 stress testing-including temperature cycling, high-temperature operating life, and unbiased highly accelerated stress testing. This makes the SMCJ75AHM3_A/H appropriate for engine control units, body electronics, and ADAS power domains.

What is the standoff voltage rating of SMCJ75AHM3_A/H and how does it relate to system design?

The SMCJ75AHM3_A/H has a reverse standoff voltage (VWM) of 75 V, meaning it remains non-conductive up to this DC or continuous AC voltage level. Designers must ensure that the maximum steady-state voltage on the protected line does not exceed 75 V to prevent premature conduction and leakage-related power loss. This rating directly informs placement decisions-for example, selecting SMCJ75AHM3_A/H for 48 V or 60 V nominal rails with margin for ripple and transients.

Does SMCJ75AHM3_A/H have polarity marking, and how is it identified?

Yes, SMCJ75AHM3_A/H is a unidirectional TVS diode with polarity clearly marked by a cathode band on the SMC (DO-214AB) package body. The banded end corresponds to the cathode terminal, which connects to the protected line (e.g., 75 V rail), while the anode connects to ground or reference. This marking is visible under standard optical inspection and aligns with IPC-A-610 acceptance criteria for polarized SMT components.

What thermal derating applies to SMCJ75AHM3_A/H above 25 °C ambient temperature?

SMCJ75AHM3_A/H exhibits linear thermal derating above 25 °C ambient: its peak pulse power (PPPM) decreases by approximately 1.2 % per °C rise, based on a junction-to-ambient thermal resistance (RθJA) of 75 °C/W and standard 8 mm × 8 mm copper pad layout. At 70 °C ambient, the effective PPPM drops to ~825 W. Derating curves are provided in Figure 2 of the official Vishay datasheet 88394 for precise system-level thermal modeling.