Diodes Incorporated AL5890-40D-13

Overview

AL5890-40D-13 from Diodes Incorporated is a 40mA fixed-output, 400V-rated linear constant-current LED driver in TO252 (Standard) package, designed for high-side or low-side series connection with LED strings. It delivers ±2.0mA (typ.) current accuracy over −40°C to +105°C ambient, features thermal foldback activation at +130°C junction temperature, and requires no external current-setting resistor. It enables long-chain commercial lighting up to 400V, subject to thermal limits of the TO252 package.

For engineers reviewing the AL5890-40D-13 datasheet, AL5890-40D-13 pinout, AL5890-40D-13 application, or AL5890-40D-13 equivalent, key selection criteria include its 40mA pre-set output, 7V turn-on threshold, thermal foldback behavior, TO252 thermal resistance (θJA = 26.12°C/W), and compatibility with AC/DC high-side/low-side configurations.

Technical Context

The AL5890-40D-13 operates as a two-terminal linear current regulator using an internal bandgap reference and voltage-controlled current source. Its functional block includes a precision current mirror and thermal foldback circuitry that linearly reduces output current above +130°C junction temperature.

It supports both AC and DC input topologies - in high-side configuration, IN connects to supply and OUT to LED anode; in low-side, IN connects to LED cathode and OUT to ground. Turn-on occurs when VIN−OUT exceeds 7V, and it sustains operation up to 400V differential while maintaining <±2.0mA current tolerance across −40°C to +105°C ambient.

Key Specifications

Pinout & Package

AL5890-40D-13 is housed in TO252 (Standard) surface-mount package with exposed thermal pad (pin 2). The device has two active terminals and one NC terminal: Pin 1 (IN) is the LED current input, Pin 2 (OUT) is the LED current output, and Pin 3 is Not Connected.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with AL5809-40D-13 and NSI45040AZT1G, the AL5890-40D-13 uniquely supports 400V operation with thermal foldback-making it the only option for robust, transformerless AC-line LED drivers requiring safety-critical thermal management in commercial luminaires.

Availability

AL5890-40D-13 is available at Aetrix Electronics and suitable for commercial LED lighting fixtures, emergency lighting systems, and architectural lighting applications requiring stable component supply, long-term production continuity, and RoHS-compliant sourcing.

Supply support for AL5890-40D-13 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 power management, signal integrity, and lighting solutions for industrial, consumer, and automotive markets.

The AL5890 product line delivers cost-effective, two-terminal constant-current LED drivers optimized for transformerless AC/DC lighting designs-targeting applications where simplicity, thermal resilience, and regulatory compliance are critical.

FAQ

What is the minimum input-to-output voltage required for AL5890-40D-13 to regulate?

The AL5890-40D-13 requires a minimum voltage difference of 7V between IN and OUT pins to initiate regulation. Below this threshold, the device remains off and conducts negligible current. This ensures stable startup even under low-line conditions and avoids flicker in dimmed or brownout scenarios.

Can AL5890-40D-13 be used in high-side configuration with AC input?

Yes-AL5890-40D-13 supports high-side AC operation when paired with a bridge rectifier. In this configuration, IN connects to the rectified positive rail and OUT connects to the LED string anode, allowing the device to regulate current regardless of AC polarity. Layout must ensure proper creepage/clearance for 400V working voltage.

How does thermal foldback behave in AL5890-40D-13?

At junction temperatures exceeding +130°C, AL5890-40D-13 linearly reduces output current to limit power dissipation. For example, at +140°C TJ, current drops to ~36mA; at +150°C, it falls to ~32mA. This self-protecting behavior prevents thermal runaway without external circuitry, enhancing reliability in sealed fixtures.

Is AL5890-40D-13 compatible with PWM dimming?

No-AL5890-40D-13 is a linear constant-current regulator without enable or dimming control pins. It cannot be directly PWM-dimmed. For dimming, designers must use external MOSFET switching in series with the LED string or implement analog dimming via variable input voltage (within 7–400V range), though accuracy degrades outside nominal conditions.