Diodes Incorporated AL5817MP-13

Overview

AL5817MP-13 from Diodes Incorporated is an 8-terminal linear LED controller IC designed to drive external bipolar transistors or MOSFETs in medium-to-high-current LED applications. It operates from 4.5V to 60V input, delivers up to 15mA output drive current, features 0.4V internal reference voltage with ±4% tolerance, and supports thermal fold-back via NTC on VSET. It is used in automotive rear combination lights and instrumentation illumination.

For engineers reviewing the AL5817MP-13 datasheet, AL5817MP-13 pinout, AL5817MP-13 application, or AL5817MP-13 equivalent, key selection criteria include its 2.5V VFAULT open-load detection threshold, PWM dimming capability via ENB or VFAULT pins, 4.2V UVLO rising threshold, and MSOP-8EP thermal performance (θJA = 90°C/W).

Technical Context

The AL5817MP-13 implements a precision current-regulation loop using an internal error amplifier with 50kHz bandwidth and 4A/V transconductance, where FB is regulated to match VSET. Its VSET pin accepts 0–0.6V input to set LED current via resistor divider from REF (0.4V ±4%), enabling configurable thermal fold-back when paired with NTC.

VFAULT provides dual-function operation: it sources –15µA and triggers output disable when pulled below 2.5V (±130mV hysteresis) for open-LED detection, and accepts open-drain PWM signals for dimming. ENB enables low-frequency PWM control with 85µs turn-on and 1µs turn-off delay.

Key Specifications

Pinout & Package

The AL5817MP-13 is housed in a thermally enhanced MSOP-8EP package with exposed pad (EP) for GND-connected thermal dissipation. The EP must be soldered to a large-area contiguous copper GND plane; it is not a substitute for electrical GND connection at Pin 4.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear LED controller applications.

Compared with AL5817MP-13, AL5816MP-13 omits critical open-circuit protection, while LM3409MMX/NOPB trades simplicity and EMI cleanliness for efficiency-making AL5817MP-13 optimal for thermally constrained, multi-string automotive and signage designs requiring robust fault handling.

Availability

AL5817MP-13 is available at Aetrix Electronics and suitable for automotive rear lighting, LED signage, instrumentation backlighting, and refrigerator interior lighting requiring stable component supply and long-term lifecycle support.

Supply support for AL5817MP-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 automotive and industrial markets.

The AL5817 belongs to Diodes' linear LED controller product line, engineered specifically for thermally demanding, multi-string LED applications where precision current regulation, open-load safety, and flexible dimming are mandatory.

FAQ

What is the maximum allowable voltage on the VFAULT pin?

The absolute maximum rating for VFAULT is –0.3V to VCC. In normal operation, it sources –15µA and is pulled down by external circuitry during open-LED faults. Exceeding VCC risks latch-up or permanent damage; a series resistor is recommended if interfacing with higher-voltage logic.

Can AL5817MP-13 drive multiple LED strings without external op-amps?

Yes-by connecting sense resistors from each string to a common node tied to FB, and using matched transistors and resistors, AL5817MP-13 regulates total current across parallel strings. No external amplifiers are needed, but matching component tolerances ≤1% is required for ≤5% current imbalance.

How does thermal fold-back work with the NTC network on VSET?

An NTC placed in the REF–VSET resistor divider reduces VSET voltage as temperature rises, lowering the FB regulation target and thus LED current. This prevents thermal runaway in enclosed fixtures. The fold-back slope is set by NTC β-value and divider ratio, with typical reduction of 1–2%/°C above 60°C.

Is the MSOP-8EP package lead-free and RoHS-compliant?

Yes-AL5817MP-13 is fully RoHS 3 compliant (2015/863/EU), halogen- and antimony-free, and lead-free per EU Directive 2002/95/EC. The exposed pad contains no lead; all terminations meet <1000ppm antimony and <900ppm bromine/chlorine limits.