Triple LED Driver in 4mm Г— 5mm QFN Supports LCD
Backlights in Buck, Boost or Buck-Boost Modes and
Delivers 3000:1 PWM Dimming Ratio
Design Note 449
Hua (Walker) Bai
Introduction
By integrating three independent LED drivers, the LTВ®3496
offers a highly efficient, compact and cost-effective
solution to drive multiple LED strings. All three drivers
have independent on/off and PWM dimming control, and
can drive different numbers or types of LEDs. High side
current sensing and built-in gate drivers for PMOS LED
disconnect allow the LT3496 to operate in buck, boost,
SEPIC or buck-boost modes with up to 3000:1 True Color
PWMв„ў dimming ratio.
The LT3496 is offered in a single 4mm Г— 5mm QFN or
FE28 package. The efficiency of each driver can exceed
95%. Integrated PMOS Drivers Improve PWM Dimming
Ratio to 3000:1
A high PWM dimming ratio is critical in many display
applications, especially in high end LCD panels. Beware,
though, the definition of dimming ratio varies among
suppliers. When comparing dimming ratios, pay close …