Vishay General Semiconductor - Diodes Division 1.5SMC18AHE3_A/I

Overview

1.5SMC18AHE3_A/I from Vishay General Semiconductor is a unidirectional transient voltage suppressor (TVS) diode designed for robust overvoltage protection in power and signal lines. It features a 18 V breakdown voltage (V_BR min/max = 17.1–18.9 V at 1 mA), 15.3 V stand-off voltage (V_WM), clamps to ≤25.2 V at 59.5 A peak pulse current (10/1000 µs), and delivers 1500 W peak pulse power in the SMC (DO-214AB) package - deployed in automotive ECUs, industrial I/O modules, and DC power input stages.

For engineers reviewing the 1.5SMC18AHE3_A/I datasheet, 1.5SMC18AHE3_A/I pinout, 1.5SMC18AHE3_A/I application, or 1.5SMC18AHE3_A/I equivalent, key selection criteria include its AEC-Q101 qualification, low clamping ratio (VC/VBR ≈ 1.33), 1.0 µA max reverse leakage at V_WM, MSL Level 1 rating, and compatibility with automated SMT placement on standard 8 mm × 8 mm copper pads.

Technical Context

This unidirectional TVS operates as a voltage-clamped shunt protector: under normal bias it presents high impedance (<1.0 µA leakage at 15.3 V), then rapidly avalanches below 100 ps to limit transients induced by ESD, lightning surges, or inductive switching. Its glass-passivated junction ensures stable breakdown and low incremental surge resistance.

The device is rated for 1500 W peak pulse power (10/1000 µs waveform), derates linearly above 25 °C (R_θJA = 75 °C/W), and supports repetitive surge duty cycles up to 0.01 %. Its cathode-band polarity marking and matte tin-plated leads comply with J-STD-002 solderability and JESD201 Class 2 whisker resistance requirements.

Key Specifications

Pinout & Package

Package: SMC (DO-214AB), surface-mount, low-profile case with matte tin-plated leads; dimensions 7.11 mm × 6.22 mm × 2.62 mm (L × W × H); cathode identified by black band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ18A and 1.5KE18A, the 1.5SMC18AHE3_A/I uniquely combines AEC-Q101 qualification, 1500 W surge capacity, and MSL Level 1 compatibility - making it the only option qualified for volume automotive SMT deployment requiring both high-energy clamping and process robustness.

Availability

1.5SMC18AHE3_A/I is available at Aetrix Electronics and suitable for automotive electronic control units, industrial programmable logic controllers, and telecom power distribution systems requiring stable component supply, long-term lifecycle support, and AEC-Q101 compliance.

Supply support for 1.5SMC18AHE3_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, MOSFETs, optoelectronics, and passive components with emphasis on reliability and application-specific performance.

The 1.5SMC Series was engineered for high-power transient suppression in harsh environments - targeting automotive, industrial, and telecom applications where robustness, repeatable clamping, and AEC-Q101 validation are mandatory.

FAQ

What is the clamping voltage of the 1.5SMC18AHE3_A/I at its rated peak pulse current?

The 1.5SMC18AHE3_A/I clamps to a maximum of 25.2 V at its specified peak pulse current of 59.5 A (10/1000 µs waveform). This value is measured under standardized test conditions with the device mounted on 8.0 mm × 8.0 mm copper pads per JEDEC guidelines. The clamping voltage directly determines the maximum stress imposed on downstream circuitry during surge events, and this 25.2 V level ensures compatibility with 24 V-rated ICs and MOSFETs.

Is the 1.5SMC18AHE3_A/I AEC-Q101 qualified, and what does that mean for automotive use?

Yes, the 1.5SMC18AHE3_A/I is AEC-Q101 qualified - confirmed by its "HE3" suffix and documentation in Vishay's 88303 datasheet. This qualification validates performance across temperature cycling, high-temperature reverse bias (HTRB), accelerated life testing, and ESD (HBM ≥ 8 kV). For automotive applications, this means the 1.5SMC18AHE3_A/I is approved for use in engine compartments, body control modules, and ADAS sensors where reliability under thermal, mechanical, and electrical stress is non-negotiable.

What is the maximum reverse leakage current of the 1.5SMC18AHE3_A/I at its stand-off voltage?

The 1.5SMC18AHE3_A/I exhibits a maximum reverse leakage current of 1.0 µA at its stand-off voltage (V_WM) of 15.3 V and ambient temperature of 25 °C. This ultra-low leakage ensures minimal power loss in always-on automotive subsystems such as telematics gateways and CAN wake-up receivers, preserving battery life while maintaining effective transient immunity.

Does the 1.5SMC18AHE3_A/I have a defined moisture sensitivity level, and what reflow profile can it withstand?

Yes, the 1.5SMC18AHE3_A/I is rated MSL Level 1 per J-STD-020, with a maximum peak reflow temperature of 260 °C. This allows unlimited floor life and compatibility with standard lead-free reflow profiles (e.g., IPC/JEDEC J-STD-020) without pre-baking. The 1.5SMC18AHE3_A/I's molding compound meets UL 94 V-0 flammability requirements and its matte tin-plated leads comply with J-STD-002 solderability standards.

How does the thermal resistance of the 1.5SMC18AHE3_A/I affect its surge handling capability at elevated temperatures?

The 1.5SMC18AHE3_A/I has a typical junction-to-ambient thermal resistance (R_θJA) of 75 °C/W when mounted on minimum recommended pad layout. At ambient temperatures above 25 °C, its peak pulse power must be derated per Figure 2 in the Vishay 88303 datasheet - e.g., at 85 °C ambient, usable P_PPM drops to ~1050 W. This derating ensures safe operation without thermal runaway during repetitive surge events in high-temperature environments like under-hood automotive locations.