LED7707 Datasheet, PDF (1/48 Pages) STMicroelectronics – 6-rows 85 mA LEDs driver with boost regulator for LCD panels backlight

LED7707
6-rows 85 mA LEDs driver with boost regulator
for LCD panels backlight
Features
■ 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 μs minimum dimming time
– ±2 % current matching between rows
– LED failure (open and short-circuit)
detection
Applications
■ LCD monitors and TV panels
■ PDAs panel backlight
■ GPS panel backlight
VFQFPN-24 4x4
Description
The LED7707 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 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
over-voltage, internal MOSFET over-current and
thermal shutdown) are provided.
Table 1.
Device summary
Order codes
LED7707
LED7707TR
Package
VFQFPN-24 4x4 (exposed pad)
Packaging
Tube
Tape and reel
September 2008
Rev 1
1/48
www.st.com
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