1

LT3466-1

34661f

White LED Driver and Boost

Converter in 3mm

× 3mm

DFN Package

Figure 1. Li-Ion Powered Driver for 6 White LEDs and OLED Display

■

Independent Dimming and Shutdown Control

of the Outputs

■

±1.5% Output Voltage Accuracy (Boost Converter)

■

±4% LED Current Programming Accuracy

■

from a 3.6V Supply

× 3mm) 10-Lead DFN Package

LT

white LED driver and a boost converter in a low profile,

small footprint (3mm

× 3mm × 0.75mm) DFN package.

The LED driver can be configured to drive up to 10 White

LEDs in series and the boost converter can be used for

generating the LCD bias voltages or driving a secondary

OLED display. Series connection of the LEDs provides

identical LED currents resulting in uniform brightness and

eliminating the need for ballast resistors and expensive

factory calibration.

The LT3466-1 provides independent dimming and shut-

down control of the two converters. The operating fre-

quency can be set with an external resistor over a 200kHz

to 2MHz range. The white LED driver features a low 200mV

reference, thereby minimizing power loss in the current

setting resistor for better efficiency. The boost converter

achieves

±1.5% output voltage accuracy by the use of a

precision 0.8V reference. Protection features include out-

put overvoltage protection and internal soft-start. Wide

input supply range allows operation from 2.7V to 24V.

3V TO 5V

16V

30mA

33

µH

1

µF

1

µF1µF

6 LEDs

33

µH

SHUTDOWN

AND DIMMING

CONTROL 2

SHUTDOWN

AND DIMMING

CONTROL 1

10

Ω

24.9k

475k

34661 F01a

63.4k

CTRL1

GND

CTRL2

SW1

SW2

LT3466-1

FB1

FB2

Conversion Efficiency

OUTPUT CURRENT (mA)

0

70

75

30

25

20

34661 F01b

60

50

65

55

510

15

90

85

80

BOOST CONVERTER

LED DRIVER

DESCRIPTIO

FEATURES

APPLICATIO S

TYPICAL APPLICATIO

, LTC and LT are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners.