Diodes Incorporated AL8843EV1

Overview

AL8843EV1 from Diodes Incorporated is an LED driver evaluation board based on the AL8843 hysteresis-mode DC-DC step-down converter IC, designed to drive 1–10 series-connected LEDs at up to 2A output current from 5–40V input. It integrates a 40V NDMOS power switch, supports analog/PWM dimming via the CTRL pin, and delivers up to 97% efficiency with inherent open-circuit and short-circuit LED protection.

For engineers reviewing the AL8843EV1 datasheet, AL8843EV1 pinout, AL8843EV1 application, or AL8843EV1 equivalent, this board enables rapid validation of LED current accuracy (±4%), soft-start timing control, thermal performance under 60W load, and dual-dimming interface implementation in retrofit lighting and signage systems.

Technical Context

The AL8843EV1 implements a fixed-frequency hysteresis-controlled buck topology with internal high-side current sensing, enabling stable constant-current regulation without external compensation. Its CTRL pin serves as a multifunction terminal-accepting 0.4–2.5V analog signals for 10–100% dimming or PWM inputs (100Hz–1kHz) with logic-level thresholds (≤0.3V off, ≥2.5V full-on).

Thermal management relies on the SO-8EP package's exposed pad and PCB copper area, validated per JEDEC JESD51-1/2 with 60-minute burn-in at 20V/3LEDs. Protection features include cycle-by-cycle overcurrent detection, thermal shutdown (>150°C), and automatic recovery after LED open/short fault clearance.

Key Specifications

Availability

AL8843EV1 is available at Aetrix Electronics and suitable for LED retrofit for low-voltage halogen, illuminated signs, and low-voltage industrial lighting requiring stable component supply, repeatable thermal validation, and fast-turn prototyping support.

Supply support for AL8843EV1 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 power management, signal integrity, and LED driver solutions for industrial, consumer, and automotive markets.

The AL8843 product line targets high-efficiency, thermally robust LED drivers for mains-connected and battery-powered lighting applications where reliability, dimming flexibility, and compact form factor are critical.

FAQ

What is the default LED current setting on AL8843EV1?

The board is factory preset to 2A LED current using parallel 0.1Ω resistors (R1 and R2). This value is confirmed by the Bill of Materials on page 5 and verified in the Quick Start Guide. The current can be adjusted by changing the sense resistor network while maintaining thermal derating limits for the SO-8EP package.

How do I configure analog vs. PWM dimming on AL8843EV1?

Analog dimming requires a 470nF capacitor (C4) installed between CTRL and GND, with 0.4–2.5V applied to CTRL for 10–100% current scaling. PWM dimming requires C4 removal and a logic-compatible signal (low ≤0.3V, high ≥2.5V) applied directly to CTRL, with recommended frequency 100Hz–1kHz and duty 1–100%.

Does AL8843EV1 provide protection against LED open or short conditions?

Yes. The underlying AL8843 IC provides inherent open-circuit LED protection (disables switching when no LED load is detected) and active LED short protection (limits current during cathode-to-ground shorts). These functions are fully operational on the evaluation board and demonstrated in functional waveforms on pages 7–8 of the User Guide.

Can AL8843EV1 drive more than 10 LEDs in series?

No. The User Guide explicitly specifies "1~10 LEDs" as the supported range, constrained by the AL8843's maximum output voltage headroom and internal current-sense amplifier range. Driving >10 LEDs would exceed the practical output compliance voltage under typical forward-voltage assumptions (e.g., 3.3V × 10 = 33V), risking regulation loss or thermal overload.