Diodes Incorporated ALS8W14A

Overview

ALS8W14A from Diodes Incorporated is a unidirectional surface-mount load dump transient voltage suppressor in DO-218 package, rated for 14.0 V stand-off voltage, 15.6–17.2 V breakdown voltage at 5 mA, 23.2 V clamping voltage at 284 A (10/1000 µs), and 6600 W peak pulse power-designed specifically for automotive ECU protection against ISO 7637-2 load dump transients.

For engineers reviewing the ALS8W14A datasheet, ALS8W14A pinout, ALS8W14A application, or ALS8W14A equivalent, key selection criteria include clamping voltage margin vs. system rail tolerance, thermal resistance under sustained surge duty, junction temperature derating above +125°C, and compliance with AEC-Q101 stress testing for under-hood deployment.

Technical Context

This device operates as a unidirectional avalanche diode with anode-connected heatsink configuration, enabling high-current transient shunting without series impedance. Its low 1.8 V forward voltage at 100 A (8.3 ms half-sine) minimizes conduction loss during surge events, while its −55°C to +175°C operating junction range supports placement near power electronics in engine compartments.

The DO-218 package delivers 0.3°C/W typical junction-to-case thermal resistance, allowing direct mounting to PCB copper pour or external heatsinks. It meets ISO 16750-2 Level IV load dump test profiles (12 V system, 100 V/100 ms) when used with appropriate layout and trace width per Diodes' application guidance.

Key Specifications

Pinout & Package

Package: DO-218 plastic outline with integral heatsink tab; anode terminal connected to heatsink base; cathode marked by bar on top surface; polarity confirmed per datasheet mechanical drawing and marking "S8W14A" with cathode bar orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ14A and SMCJ14A, ALS8W14A uniquely combines 6600 W surge rating, DO-218 thermal performance, and AEC-Q101 qualification-making it the only option validated for direct integration into safety-critical automotive power rails requiring ISO 7637-2 compliance.

Availability

ALS8W14A is available at Aetrix Electronics and suitable for automotive engine control units, body control modules, ADAS camera power inputs, and electric power steering ECUs requiring stable component supply across extended production lifecycles.

Supply support for ALS8W14A 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for automotive, industrial, and computing markets with ISO/TS 16949 and IATF 16949 certified operations.

The ALS8WxxA series is part of Diodes' Automotive Transient Voltage Suppressors product line, engineered specifically to meet stringent ISO 7637-2 and ISO 16750-2 load dump requirements in under-hood environments.

FAQ

What is the maximum allowable PCB copper area for optimal thermal performance?

Diodes recommends a minimum 200 mm² (20 mm × 10 mm) of 2 oz copper connected directly to the anode heatsink tab. Larger areas improve steady-state thermal resistance, but layout must avoid thermal vias under the tab that compromise solder joint integrity per JEDEC J-STD-020 moisture sensitivity level 1 guidelines.

Does ALS8W14A require external series impedance for safe operation?

No external series resistor or inductor is required. The device is designed for direct connection across the protected rail. However, trace inductance between cathode and protected IC must be minimized (<5 nH) to prevent voltage overshoot exceeding V_C; Diodes specifies ≤3 mm length and ≥1.5 mm width for 1 oz copper traces in layout recommendations.

How does ALS8W14A perform under repeated load dump pulses?

Per DS43856 Rev. 9, ALS8W14A maintains V_BR and V_C within specification after 1000 cycles of 10/1000 µs 6600 W pulses at 1 Hz repetition rate and T_A = +85°C. No parameter shift exceeds ±5%, confirming suitability for start-stop vehicle applications with frequent alternator engagement.

Is the DO-218 package compatible with standard SMT reflow profiles?

Yes-ALS8W14A supports lead-free reflow up to +260°C for 10 seconds (JEDEC J-STD-020 Level 1). The package withstands peak temperatures without delamination or solder wicking into the heatsink tab, provided preheat ramp rate stays within 3°C/s and time above 217°C is limited to 60–90 seconds per IPC-J-STD-020.