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Boost section
鈥?4.5 V to 36 V input voltage range
鈥?Internal power MOSFET
鈥?Internal +5 V LDO for device supply
鈥?Up to 36 V output voltage
鈥?Constant frequency peak current-mode
control
鈥?250 kHz to 1 MHz adjustable switching
frequency
鈥?External synchronization for multi-device
application
鈥?Pulse-skip power saving mode at light load
鈥?Programmable soft-start
鈥?Programmable OVP protection
鈥?Stable with ceramic output capacitors
鈥?Thermal shutdown
Backlight driver section
鈥?Six rows with 30 mA maximum current
capability (adjustable)
鈥?Parallelable rows for higher current
鈥?Rows disable option
鈥?Less than 500 ns minimum dimming time
(1 % minimum dimming duty-cycle at 20
kHz)
鈥?卤2 % current matching between rows
鈥?LED failure (open and short-circuit)
detection
VFQFPN-24 4x4
Description
The LED7706 consists of a high efficiency
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 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.
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Applications
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LCD monitors and TV panels
PDA panel backlight
GPS panel backlight
Device summary
Order code
LED7706
VFQFPN-24 4x4 (exposed pad)
LED7706TR
Tape and reel
Rev 1
1/31
www.st.com
31
Table 1.
Package
Packaging
Tube
February 2008
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