AN2809 Datasheet, PDF (1/22 Pages) STMicroelectronics – The LED7706 consists of a high-efficiency monolithic boost converter and six controlled

AN2809
Application note
6-row / 30-mA LED driver with boost converter
for the backlight of LCD panels
Introduction
The LED7706 consists of a high-efficiency monolithic boost converter and six controlled
current generators (rows) specifically designed to supply the LED arrays used in the
backlights of LCD panels. The device can manage an output voltage of up to 36 V (ten white
LEDs per row).
The generators can be externally-programmed to sink up to 30 mA and can be dimmed via
a PWM signal (a 1% dimming duty-cycle at 20 kHz can be managed). The device detects
and manages the open and shorted LED faults and leaves unused rows floating. Basic
protections (output over-voltage, internal MOSFET over-current and thermal shutdown) are
provided.
Figure 1. LED7706 demonstration board
February 2009
Rev 2
1/22
www.st.com