Vishay General Semiconductor - Diodes Division SMBJ33AHE3_A/I

Overview

SMBJ33AHE3_A/I 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 33 V standoff voltage (V_WM), 36.7–40.6 V breakdown range at 1 mA, clamps transients to ≤53.3 V at 11.3 A (10/1000 µs), and delivers 600 W peak pulse power - used to safeguard MOSFET gates, microcontroller I/O, and industrial sensor interfaces against ESD and inductive switching surges.

For engineers reviewing the SMBJ33AHE3_A/I datasheet, SMBJ33AHE3_A/I pinout, SMBJ33AHE3_A/I application, or SMBJ33AHE3_A/I equivalent, this device is evaluated for automotive-grade surge immunity (AEC-Q101 qualified), low-clamping-voltage transient suppression, thermal reliability up to +150 °C junction temperature, and compatibility with automated SMT assembly on SMB (DO-214AA) footprint.

Technical Context

This unidirectional TVS operates as a voltage-clamped shunt protector: under normal bias it presents <1.0 µA leakage at 33 V, then rapidly avalanches when reverse voltage exceeds its 36.7–40.6 V V_BR window, limiting downstream voltage to ≤53.3 V at rated 11.3 A surge current. Its glass-passivated junction ensures stable breakdown characteristics and fast response (<1 ns).

Thermally, it uses an SMB (DO-214AA) package with R_θJA = 100 °C/W and R_θJL = 20 °C/W, enabling reliable operation at T_J = –55 to +150 °C. The HE3 suffix confirms RoHS compliance and AEC-Q101 qualification - critical for automotive body electronics and industrial control modules requiring long-term reliability under repetitive surge stress.

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), surface-mount, cathode-banded unidirectional configuration. Matte tin-plated leads, solderable per J-STD-002 and JESD 22-B102. Polarity marked by black band denoting cathode terminal.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ33AHM3_A/I, SMBJ33AHE3_A/I offers identical surge performance with standard RoHS compliance; versus SMCJ33AHE3_A/I, it trades lower power handling and higher thermal resistance for compact SMB footprint - optimal for space-constrained automotive modules and sensor nodes.

Availability

SMBJ33AHE3_A/I is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC analog I/O protection, and telecom DC bias line surge suppression requiring stable component supply, AEC-Q101 traceability, and consistent SMB footprint compatibility.

Supply support for SMBJ33AHE3_A/I 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, precision, and automotive qualification.

The SMBJ series is engineered for high-reliability transient suppression in automotive, industrial, and telecom systems - delivering consistent clamping performance, AEC-Q101 validation, and robust SMT manufacturability in the SMB package.

FAQ

What is the maximum clamping voltage of SMBJ33AHE3_A/I at its rated peak pulse current?

The SMBJ33AHE3_A/I clamps to a maximum of 53.3 V when subjected to its rated peak pulse current of 11.3 A under the standard 10/1000 µs waveform. This value is measured per Figure 1 and Table 1 in the Vishay datasheet 88392 and defines the upper voltage limit imposed on protected circuitry during surge events. Designers use this parameter to verify that downstream components remain within absolute maximum ratings during transient conditions.

Is SMBJ33AHE3_A/I suitable for automotive applications?

Yes, SMBJ33AHE3_A/I is AEC-Q101 qualified, as confirmed by the "HE3" suffix and documentation in Vishay's datasheet 88392. It is rated for operation from –55 °C to +150 °C junction temperature and validated for reliability under temperature cycling, humidity, and mechanical shock - making it appropriate for engine control units, body electronics, and ADAS sensor modules where automotive-grade assurance is mandatory.

What does the "A/I" suffix in SMBJ33AHE3_A/I indicate?

The "A/I" suffix in SMBJ33AHE3_A/I specifies packaging and reel configuration: "A" denotes the revision code (per Vishay's ordering nomenclature), and "I" indicates 13-inch diameter plastic tape and reel with 3200 units per reel. This matches the preferred delivery mode listed in the Ordering Information section of datasheet 88392 and ensures compatibility with high-speed pick-and-place equipment.

How does SMBJ33AHE3_A/I differ from bidirectional variants like SMBJ33CA?

SMBJ33AHE3_A/I is unidirectional, with polarity marked by a cathode band and intended for DC line protection where reverse voltage is blocked. In contrast, SMBJ33CA is bidirectional - symmetrical in both directions, no polarity marking, and used in AC-coupled or floating signal lines. Electrical parameters differ: SMBJ33CA has V_BR = 36.7–40.6 V in both directions, while SMBJ33AHE3_A/I conducts only in reverse avalanche, with forward VF ≤ 3.5 V at 50 A.

What is the thermal resistance from junction to ambient for SMBJ33AHE3_A/I?

The typical thermal resistance from junction to ambient (R_θJA) for SMBJ33AHE3_A/I is 100 °C/W, measured on a 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pad per terminal, per datasheet 88392. This value assumes standard PCB layout and natural convection cooling; designers must verify board-level thermal design if operating near maximum power dissipation or elevated ambient temperatures.