General Description
The RT8549L is a high efficiency Boost converter with
4-CH LED driver supporting 60V maximum output voltage.
It is designed for LCD panel applications that employs
LED as lighting sources. The Boost converter generates
a suitable output voltage to drive four LED strings in parallel
and supports up to 18 LEDs per string.
The RT8549L supports a wide input voltage range from
4.2V to 24V and provides a SMBus interface to control
the LED brightness dimming mode, operating frequency
and LED currents. The internal 150mΩ, 60V power switch
with current-mode control provides high efficiency
operation.
The RT8549L is available in the WDFN-16L 5x5 package
to achieve optimized solution for PCB space.

Applications
 UMPC and Notebook Computer Backlight

Features
 Wide Operating Input Voltage : 4.2V to 24V
 Max 60V Output Voltage
 3% LED Current Accuracy
 2% LED Current Matching
 Low Drop Output 120mA/0.4V Current Sink
 SMBus Programs LED Current, Switching
Frequency, Dimming Mode
 LED Current : 22.58mA to 180mA
 Switching Frequency : 200kHz to 900kHz
 Dimming Mode : PWM, DC, Mixed-Mode
 Built-in Input UVP, Output OVP, OCP, and Soft-Start
 Support LED Hot-plug, Open/Short Detection
 Low EMI, Low Acoustic Noise
 16-Load WDFN Package
 RoHS Compliant and Halogen Free