STMicroelectronics LED7706

The LED7706 consists of a high efficiency monolithic boost converter and six controlled current generators (rows) specifically designed to supply LEDs 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 30 mA and can be dimmed via a PWM signal (1 % dimming duty-cycle at 20 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 over-voltage, internal MOSFET over-current and thermal shutdown) are provided.

Key features

• 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
• Six rows with 30 mA maximum current capability (adjustable)
• Rows disable option
• Less than 500 ns minimum dimming ontime (1 % minimum dimming duty-cycle at 20 kHz)
• ±2 % current matching between rows
• LED failure (open and short-circuit) detection

Applications

• LCD monitors and TV panels
• PDAs panel backlight
• GPS panel backlight