1FEATURES
2• 91% Peak LED Drive Efficiency
• No Inductor Required
• 0.3% Current Matching
• Drives 6 LEDs with up to 30mA per LED
• 180mA of total driver current
• I2C Compatible Brightness Control Interface
• Adaptive 1×- 3/2× Charge Pump
• Resistor-Programmable Current Settings
• External Chip RESET Pin (RESET)
• Extended Li-Ion Input: 2.7V to 5.5V
• Small low profile industry standard leadless
package, WQFN 24 : (4mm x 4mm x 0.8mm)

APPLICATIONS
• Mobile Phone Display Lighting
• PDAs Backlighting
• General LED Lighting

DESCRIPTION
The LM27966 is a highly integrated charge-pump-
based display LED driver. The device can drive up to
6 LEDs in parallel with a total output current of
180mA. Regulated internal current sources deliver
excellent current and brightness matching in all LEDs.
The LED driver current sources are split into two
independently controlled groups. The primary group,
which can be configured with 4 or 5 LEDs, can be
used to backlight the main phone display. An
additional, independently controlled led driver is
provided for driving an indicator or other general
purpose LED function. The LM27966 has an I2C compatible interface that allows the user to
independently control the brightness on each bank of
LEDs.
The device provides excellent efficiency without the use of an inductor by operating the charge pump in a
gain of 3/2, or in Pass-Mode. The proper gain for
maintaining current regulation is chosen, based on
LED forward voltage, so that efficiency is maximized
over the input voltage range.
The LM27966 is available in a small 24-pin Leadless
Leadframe WQFN-24 package.