Vishay General Semiconductor - Diodes Division SMBJ7.5CHE3/5B

Overview

SMBJ7.5CHE3/5B from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMB (DO-214AA) package, designed for clamping voltage transients on power and signal lines. It features 7.5 V stand-off voltage (V_WM), 8.33–9.21 V breakdown voltage (V_BR) at 1.0 mA, 12.9 V maximum clamping voltage (V_C) at 46.5 A peak pulse current, and 600 W peak pulse power rating with 10/1000 µs waveform - used to protect MOSFETs, ICs, and sensor interfaces in industrial power supplies.

For engineers reviewing the SMBJ7.5CHE3/5B datasheet, SMBJ7.5CHE3/5B pinout, SMBJ7.5CHE3/5B application, or SMBJ7.5CHE3/5B equivalent, key selection criteria include unidirectional polarity, AEC-Q101 qualification status, 12.9 V clamping performance at rated surge current, thermal resistance (R_θJA = 100 °C/W), and RoHS-compliant matte tin-plated leads suitable for automated SMT assembly.

Technical Context

This TVS diode operates as a fast-acting shunt protector: under normal bias it presents high impedance (<100 µA leakage at 7.5 V), then avalanches within <1 ns when transient voltage exceeds V_BR, clamping the line to ≤12.9 V while diverting up to 46.5 A (10/1000 µs). Its glass-passivated junction ensures stable breakdown and low incremental surge resistance.

The SMBJ7.5CHE3/5B variant is AEC-Q101 qualified and marked with HE3 suffix, indicating automotive-grade reliability; its SMB package supports 0.2" × 0.2" copper pad layout per JEDEC standards, enabling thermal dissipation up to 5.0 W at T_A = 50 °C with R_θJL = 20 °C/W to lead.

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), surface-mount, low-profile case with matte tin-plated leads solderable per J-STD-002 and JESD 22-B102; cathode indicated by band marking on unidirectional device.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ7.5AHE3/5B and SMAJ7.5AHE3/5B, the SMBJ7.5CHE3/5B uniquely combines AEC-Q101 qualification, 600 W surge capacity, and SMB package thermal performance - making it the only option qualified for automotive power rail protection where both reliability and energy handling are mandatory.

Availability

SMBJ7.5CHE3/5B is available at Aetrix Electronics and suitable for automotive power systems, industrial sensor interfaces, consumer DC adapters, and MOSFET gate protection requiring stable component supply across production lifecycles.

Supply support for SMBJ7.5CHE3/5B 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 SMBJ series is part of Vishay's TRANSZORB® TVS platform, engineered for robust transient suppression in automotive, industrial, and communications infrastructure where failure modes must be mitigated without compromising signal integrity or thermal stability.

FAQ

What is the polarity configuration of SMBJ7.5CHE3/5B?

The SMBJ7.5CHE3/5B is a unidirectional TVS diode, with cathode identified by the band marking on the SMB package body. It conducts only when the cathode is biased positively relative to the anode - making it suitable for DC line protection where polarity is fixed, such as 12 V automotive rails or regulated DC outputs. This differs from bidirectional variants (e.g., SMBJ7.5CHE3/5B does not conduct symmetrically in both directions).

Does SMBJ7.5CHE3/5B meet automotive qualification standards?

Yes, SMBJ7.5CHE3/5B is AEC-Q101 qualified, as confirmed by the "HE3" suffix in its ordering code and Vishay documentation. This qualification covers stress tests including high-temperature reverse bias, temperature cycling, and accelerated life testing - validating its use in engine control units, body electronics, and ADAS modules where reliability under harsh conditions is required.

What is the maximum clamping voltage of SMBJ7.5CHE3/5B under rated surge conditions?

The SMBJ7.5CHE3/5B has a maximum clamping voltage (V_C) of 12.9 V at 46.5 A peak pulse current (10/1000 µs waveform), as specified in Vishay's datasheet revision 09-Jan-2024. This value represents the upper limit of voltage seen by protected circuitry during worst-case transient events and is critical for ensuring compatibility with downstream components rated for ≤13.2 V absolute maximum.

How does the SMB package of SMBJ7.5CHE3/5B affect thermal performance?

The SMB (DO-214AA) package of SMBJ7.5CHE3/5B provides a thermal resistance of R_θJA = 100 °C/W on standard 0.2" × 0.2" copper pads and R_θJL = 20 °C/W to lead, enabling 5.0 W power dissipation at T_A = 50 °C. Its larger footprint versus SMA improves heat spreading, allowing sustained operation in high-ambient environments like under-hood automotive or enclosed industrial enclosures where thermal margin is limited.

Can SMBJ7.5CHE3/5B be used for bidirectional signal line protection?

No, SMBJ7.5CHE3/5B is unidirectional and not suitable for bidirectional signal lines such as RS-485 or USB D+/D− without additional circuitry. For such applications, a bidirectional variant like SMBJ7.5CHE3/5B would be required - but that part does not exist; the correct alternative is SMBJ7.5CAHE3/5B. Using SMBJ7.5CHE3/5B on AC-coupled or floating lines risks forward conduction during negative half-cycles, potentially damaging the device or distorting signals.