23-12-2024 | Diodes Inc | Lighting Technologies
Diodes Incorporated has announced the expansion of its automotive-compliant LED driver portfolio with the AL8891Q. This easy-to-use synchronous Buck LED driver with high-side current sense drives up to 2A from a wide 4.5V to 65V input voltage range. It supports up to 95% duty cycle, enabling the drive of longer LED chains. The device delivers a flexible, high-efficiency solution for automotive lighting applications, including DRL, fog lights, turn lights, brake/stop lights, and interior lights.
Using COT control, the device achieves simple control-loop compensation and cycle-by-cycle current limiting with a fast transient response without needing an external compensation capacitor. The device’s switching frequency is adjustable from 200kHz to 2.5MHz, allowing it to optimise efficiency or attain a smaller inductor size and compact form factor. It includes a spread spectrum frequency modulation technique to improve EMI performance, which eases compliance with the most stringent CISPR 25 Class 5 standard.
The device has two independent pins – PWM and analog dimming – for improved functionality. PWM dimming, from 0.1kHz to 2kHz, is suited to high-resolution dimming, and analog dimming is from 0.15V to 2V. It features an internal soft-start function, gradually increasing the inductor and switch current to minimise potential overvoltage and overcurrent at the output.
The device features comprehensive protections with fault reporting, including thermal shutdown with auto-restart, input and constant current UVLO, cycle-by-cycle current limit, and LED-open and short-circuit protection to help increase system robustness.
The AL8891Q is offered in the thermally enhanced TSSOP-16EP package and has an operating temperature range of -40C to +125C. A standard compliance version, AL8891, is also available and is suited to industrial and commercial applications.
