Diodes Incorporated AL8859Q FlexPhase SPI Boost Controllers

Diodes Inc. AL8859Q FlexPhase SPI Boost Controllers are integrated two-phase SPI-controlled boost controllers designed for high‑power, high‑efficiency applications. The Diodes Inc. AL8859Q functions as the primary stage in advanced power architectures, including adaptive automotive LED lighting systems that integrate high beam, low beam, daytime running lights (DRL), turn indicators, fog lamps, static cornering lights, and other features. When paired with a secondary stage of high‑current LED drivers, the AL8859Q enables a complete lighting module solution capable of powering multiple LED strings. The SPI‑based digital interface supports simple software updates and configuration adjustments, ensuring flexibility across a wide range of system designs and application platforms.

These Diodes Inc. devices operate as current‑mode, voltage‑boost controllers that also serve as an input filter, minimizing external component requirements. The output voltage is fully programmable through SPI. Up to two devices can be combined in multi‑phase configurations (1‑, 2‑, 3‑, or 4‑phase) to enhance filtering performance and reduce BOM cost for high‑power systems. The AL8859Q is available in a wettable‑flank V‑QFN4040‑24/SWP package (4mm × 4mm), offering improved solderability and enhanced reliability.

Features

AEC-Q100 Grade 1
Functional safety-capable
Wide 4.5V to 60V input voltage range
±0.5% typical output voltage accuracy at 50V
Soft-start and high 95% efficiency
SPI programmable features
- Up to 4-phase control
- Output-voltage regulation
- Programmable switching frequency
- Switching current limit, overvoltage
- Diagnostic and protection registers
- One-time programming (OTP)

Spread spectrum to improve EMI
Fail-safe operating (FSO) mode, stand-alone mode
Wettable V-QFN4040-24/SWP package (4mm × 4mm)
Totally lead-free and fully RoHS-compliant
Halogen and antimony-free, Green device
Suitable for automotive applications requiring specific change control - AEC-Q100 qualified, PPAP capable, and manufactured in IATF 16949 certified facilities

Applications

Adaptive LED headlights, DRL, and fog lamps
Hybrid powertrains
Actuators and pumps

Integrated USB port systems (IUPS)
Audio and infotainment
ADAS and radars

Specifications

4.5V to 60V battery supply voltage range on the VBB pin
3.1V to 3.5V logic supply voltage range
1mA to 50mA V_DD supply current range
0V to 5V medium voltage I/O pins range
-0.1V to 1V input current-sense voltage range
60mA to 350mA output current limitation range
1μA maximum shutdown supply current
7MHz to 13MHz system oscillator frequency range
-40°C to +150°C operating junction temperature range
-40°C to +125°C operating ambient temperature range

Thermal
- 31.2°C/W junction-to-ambient thermal resistance
- 27.2°C/W junction-to-case (top) thermal resistance
- 1.13°C/W junction-to-case (bottom) thermal resistance
- 11.1°C/W junction-to-board thermal resistance
- 0.18°C/W junction-to-top characterization parameter
- 10.78°C/W junction-to-board characterization parameter
ESD ratings
- 2000V Human Body Model (HBM)
- 750V Charged Device Model (CDM)