Diodes Incorporated AL5809-25QP1-7

Overview

AL5809-25QP1-7 from Diodes Incorporated is an AEC-Q100 Grade 1 qualified, two-terminal linear constant current LED driver delivering a precise 25mA ±5% output over -40°C to +150°C junction temperature, with 2.5V–60V operating voltage range and 20ppm/°C temperature stability. It supports both high-side and low-side LED string configurations in automotive interior lamps and instrumentation illumination.

For engineers reviewing the AL5809-25QP1-7 datasheet, AL5809-25QP1-7 pinout, AL5809-25QP1-7 application, or AL5809-25QP1-7 equivalent, key selection criteria include guaranteed current accuracy across automotive temperature extremes, thermal shutdown at +165°C with +30°C hysteresis, PowerDI123 (Type B) package thermal performance (θJA = 81.4°C/W on 50.8mm × 50.8mm GETEK), and compatibility with PWM dimming down to 500µs minimum pulse width.

Technical Context

The AL5809-25QP1-7 integrates a fixed internal current-setting resistor and precision current mirror to deliver stable 25mA regulation without external components. Its low-dropout internal LDO powers the control block, enabling operation down to 2.5V VINOUT while maintaining ±5% accuracy from -40°C to +150°C.

It features thermal shutdown activation at +165°C with +30°C hysteresis, 80V absolute maximum input-output voltage rating, and 4kV HBM ESD protection. The device turns on when VINOUT exceeds ~1.5V and sustains up to 1.5W power dissipation in the PowerDI123 (Type B) package under optimized PCB layout.

Key Specifications

Pinout & Package

Package: PowerDI123 (Type B) - thermally robust surface-mount package with exposed cathode pad, 3.7mm × 2.8mm footprint, 1.78mm height, and optimized thermal vias capability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AL5809-20QP1-7 and AL5809-30QP1-7, the AL5809-25QP1-7 delivers optimal balance of photometric output, thermal margin, and LED lifetime for mid-brightness automotive interior and signaling functions - avoiding underdrive inefficiency or overdrive reliability risk.

Availability

AL5809-25QP1-7 is available at Aetrix Electronics and suitable for automotive interior lamps, instrumentation illumination, and parking light systems requiring stable component supply, AEC-Q100 compliance, and PPAP-ready documentation.

Supply support for AL5809-25QP1-7 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 lighting solutions for automotive, industrial, and consumer markets.

The AL5809Q product line delivers AEC-Q100 qualified two-terminal constant current regulators targeting cost-sensitive, space-constrained automotive LED lighting where simplicity, thermal robustness, and transient immunity are critical.

FAQ

What is the minimum input voltage required for AL5809-25QP1-7 to begin regulating?

The AL5809-25QP1-7 begins current regulation once the voltage across its IN and OUT terminals reaches approximately 1.5V, with a typical startup threshold of 1.5V and a guaranteed range of 1.0V to 2.0V across -40°C to +150°C. This ensures reliable turn-on during automotive cold-cranking events where battery voltage may dip to 9V, provided the LED string forward voltage remains below 7.5V (9V – 1.5V).

Can AL5809-25QP1-7 be used in high-side configuration with common-anode LED strings?

Yes - the AL5809-25QP1-7 supports high-side configuration: connect the LED anode to the OUT pin and the LED cathode to the system ground or current return path, while applying supply voltage to the IN pin. This places the regulated 25mA current source between the supply rail and the LED anode, enabling direct integration into existing high-side driver architectures without level-shifting circuitry.

How does thermal shutdown behave during sustained overload conditions?

When junction temperature reaches +165°C, the AL5809-25QP1-7 disables current flow and enters thermal shutdown. It remains off until temperature drops by ≥30°C (to ≤+135°C), then automatically resumes regulation. This hysteresis prevents oscillation during marginal thermal conditions and protects against permanent damage during prolonged overvoltage or inadequate PCB heatsinking.

Is AL5809-25QP1-7 compatible with PWM dimming using an external MOSFET?

Yes - the AL5809-25QP1-7 supports PWM dimming via external switching: for high-side LEDs, place an N-channel MOSFET between the OUT pin and ground; for low-side LEDs, use a P-channel MOSFET between supply and IN pin. The device tolerates 100–200Hz square-wave gating with minimum 500µs ON and OFF pulses, enabling smooth 5–95% duty-cycle brightness control without affecting current accuracy.