The ALED7707 device consists of an automotive grade (AEC Q100 compliant) monolithic boost converter and six controlled current generators (rows) specifically designed to supply LED arrays used in the backlighting of LCD panels. The device can manage an output voltage up to 36 V (i.e.: 10 white LEDs per row). The generators can be externally programmed to sink up to 85 mA and can be dimmed via a PWM signal (1% dimming duty cycle at 1 kHz can be managed). The device allows to detect and manage the open and shorted LED faults and to let unused rows floating. Basic protections (output overvoltage, internal MOSFET overcurrent and thermal shutdown) are provided.
Boost section 4.5 V to 36 V input voltage range Internal power MOSFET Internal +5 V LDO for device supply Up to 36 V output voltage Constant frequency peak current-mode control 250 kHz to 1 MHz adjustable switching frequency External synchronization for multi-device application Pulse skip power saving mode at light load Programmable soft-start Programmable OVP protection Stable with ceramic output capacitors Thermal shutdown Backlight driver section Six rows with 85 mA maximum current capability (adjustable) Rows disable option Less than 10 us minimum dimming on-time ± 3% current matching between rows LED failure (open and short-circuit) detection