Diodes Incorporated AL5871QT16E-13

Overview

AL5871QT16E-13 from Diodes Incorporated is an AEC-Q100 qualified automotive-grade single-channel linear LED driver with PWM and analog dimming control, 5V–55V input range, ±4% LED current accuracy, and integrated UVLO, OTP, LED open/short protection. It delivers up to 750mA output current and enters automatic standby mode when PWM is inactive, targeting dome lights and rear lamps in passenger vehicles.

For engineers reviewing the AL5871QT16E-13 datasheet, AL5871QT16E-13 pinout, AL5871QT16E-13 application, or AL5871QT16E-13 equivalent, key selection criteria include thermal foldback threshold (135°C), FAULTB diagnostic reporting, DEN-configurable open-detection enable, and RREF-based current setting (e.g., 24kΩ → 750mA).

Technical Context

The AL5871QT16E-13 uses a precision bandgap-referenced current regulation architecture with internal pre-regulator and PWM-controlled current sink. Its analog dimming path accepts 0.3–1.5V on ADIM for linear 0–100% current scaling, while PWM dimming operates at 200Hz–1kHz with <1% duty-cycle linearity error.

Protection logic integrates independent deglitch timers (5ms open, 5ms short), hiccup-mode recovery (128ms), and dual-threshold thermal management: foldback begins at +135°C (reducing current to 50% at +160°C), and full shutdown triggers at +160°C with restart at +130°C.

Key Specifications

Pinout & Package

TSSOP-16EP (Type DX) package with exposed thermal pad internally connected to GND; requires external GND connection and thermal vias for θJA = 42.7°C/W performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AL5871QT16E-13, AL5873QT16E-13 adds channel independence without sacrificing thermal robustness, while ASL3416SHN trades analog/PWM flexibility for digital configurability and system-level diagnostics-making AL5871QT16E-13 optimal for cost-sensitive, single-string automotive lighting with minimal MCU overhead.

Availability

AL5871QT16E-13 is available at Aetrix Electronics and suitable for automotive interior lighting, exterior signaling, and EV charging indicator applications requiring stable component supply, AEC-Q100 compliance, and long-term production continuity.

Supply support for AL5871QT16E-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 ICs, specializing in high-reliability power management, signal integrity, and automotive solutions.

The AL5871Q belongs to Diodes' automotive LED driver product line, engineered specifically for robust, thermally adaptive constant-current control in space-constrained lighting modules operating across harsh automotive voltage and temperature ranges.

FAQ

What is the minimum LED forward voltage the AL5871QT16E-13 can regulate?

The AL5871QT16E-13 maintains regulation down to 0.2V at 125mA output current, enabling use with ultra-low-Vf LEDs or short strings in tight thermal envelopes. This low dropout is achieved via optimized internal pass transistor design and referenced directly in the Electrical Characteristics table (VLED_REG parameter).

How does the DEN pin affect open-circuit detection and thermal foldback?

DEN pin voltage independently configures two functions: ≥1.2V enables LED open detection, <1.1V disables it to prevent false triggers during low-dropout operation; ≥0.3V enables thermal foldback, <0.2V disables it. These thresholds are specified in the Pin Descriptions section and validated across temperature.

Can AL5871QT16E-13 operate without a microcontroller?

Yes-AL5871QT16E-13 supports standalone operation using only PWM and ADIM signals: PWM toggles LED on/off, ADIM sets analog brightness level (0.3–1.5V), and FAULTB provides passive fault indication. No communication interface or firmware is required for basic functionality.

What PCB layout practices ensure optimal thermal performance?

Mount the exposed pad to a dedicated GND plane with ≥6 thermal vias (0.3mm diameter, 0.8mm pitch); use 2oz copper on top/bottom layers; maintain ≥2"×2" thermal land area. This achieves the datasheet-specified θJA of 42.7°C/W and prevents thermal foldback under continuous 750mA load.