Vishay General Semiconductor - Diodes Division SMBJ12AHE3_B/H

Overview

SMBJ12AHE3_B/H from Vishay General Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode designed for robust overvoltage protection in power rails and signal lines. It features a 12 V standoff voltage (VWM), 13.3–14.7 V breakdown range at 1 mA, 19.9 V clamping voltage at 30.2 A peak pulse current (10/1000 μs), and 600 W peak pulse power dissipation - deployed to safeguard MOSFETs, ICs, and sensor interfaces in industrial motor drives and telecom power supplies.

For engineers reviewing the SMBJ12AHE3_B/H datasheet, SMBJ12AHE3_B/H pinout, SMBJ12AHE3_B/H application, or SMBJ12AHE3_B/H equivalent, key selection criteria include its AEC-Q101 qualification status, SMB (DO-214AA) package compatibility with automated SMT placement, low incremental surge resistance, and verified clamping performance under repetitive 0.01% duty-cycle transients.

Technical Context

This TVS diode operates as a unidirectional clamping device with cathode-band polarity marking. Its silicon junction is glass passivated for stable leakage and long-term reliability, and it meets MSL Level 1 per J-STD-020 with 260 °C lead-free reflow capability.

The SMBJ12AHE3_B/H delivers consistent clamping response within 1 ns typical, supports 100 A non-repetitive forward surge (8.3 ms half-sine), and maintains thermal stability up to 150 °C junction temperature with R_θJA = 100 °C/W on standard 0.2" × 0.2" copper pads.

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), 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 SMBJ12AHE3_B/H, SMBJ12AE3/52 reduces qualification overhead but forfeits automotive traceability, while SMCJ12AHE3_A/H trades compactness for enhanced surge headroom and thermal performance - making SMBJ12AHE3_B/H optimal for space-constrained AEC-Q101-compliant 12 V rail protection.

Availability

SMBJ12AHE3_B/H is available at Aetrix Electronics and suitable for industrial motor control, automotive body electronics, and telecom power supply designs requiring stable component supply, AEC-Q101 compliance, and repeatable 600 W transient suppression performance.

Supply support for SMBJ12AHE3_B/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, rectifiers, MOSFETs, and protection devices with emphasis on reliability, efficiency, and application-specific validation.

The SMBJ series targets board-level transient protection in automotive, industrial, and telecom systems, engineered for fast clamping, low leakage, and seamless integration into automated SMT manufacturing flows.

FAQ

What is the maximum clamping voltage of SMBJ12AHE3_B/H under standard test conditions?

The SMBJ12AHE3_B/H has a maximum clamping voltage (VC) of 19.9 V when subjected to a 30.2 A peak pulse current with a 10/1000 μs waveform. This value is measured at TA = 25 °C and reflects the upper limit of voltage imposed on the protected circuit during a defined surge event - critical for ensuring downstream ICs remain within absolute maximum ratings. The SMBJ12AHE3_B/H maintains this clamping performance across its qualified operating temperature range.

Is SMBJ12AHE3_B/H suitable for automotive applications?

Yes, SMBJ12AHE3_B/H is AEC-Q101 qualified, meaning it has passed rigorous stress tests including temperature cycling, high-temperature reverse bias, and ESD verification required for automotive electronic modules. Its RoHS-compliant construction, MSL Level 1 rating, and 150 °C maximum junction temperature make it appropriate for under-hood and cabin-mounted systems such as body control units and infotainment power rails - all confirmed in Vishay's official qualification report referenced in Document Number 88392.

What does the "HE3" suffix indicate in SMBJ12AHE3_B/H?

The "HE3" suffix in SMBJ12AHE3_B/H denotes a RoHS-compliant, AEC-Q101-qualified version with matte tin-plated leads and JESD 201 Class 2 whisker resistance. The "_B/H" indicates packaging in 7" diameter tape-and-reel format (H = reel size code) with revision B. This distinguishes it from commercial-grade variants like SMBJ12AE3/52 and halogen-free alternatives such as SMBJ12AHM3_B/H - all defined in Vishay's official ordering information table on page 3 of document 88392.

How does SMBJ12AHE3_B/H compare to bidirectional TVS diodes like SMBJ12CA?

SMBJ12AHE3_B/H is unidirectional and intended for DC rail protection where polarity is fixed (e.g., +12 V to ground), offering lower leakage and tighter VBR tolerance than bidirectional counterparts. In contrast, SMBJ12CA provides symmetrical clamping for AC or floating signal lines but exhibits double the ID at VWM and slightly higher VC due to dual-junction architecture. The cathode band on SMBJ12AHE3_B/H simplifies layout verification - a key distinction confirmed in Vishay's "Polarity" section on page 1 of document 88392.

What is the thermal resistance of SMBJ12AHE3_B/H, and how does it affect PCB layout?

SMBJ12AHE3_B/H has a typical junction-to-ambient thermal resistance (R_θJA) of 100 °C/W when mounted on 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal. This value assumes minimum recommended pad layout per Vishay's mechanical drawing on page 5. To maintain safe junction temperatures below 150 °C during repetitive surges, designers must allocate adequate copper area and avoid excessive trace length - especially critical in high-duty-cycle applications like motor drive snubbers where thermal accumulation occurs.