LT3598

1

3598fa

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

6-String 30mA LED Driver

with 1.5% Current Matching

designed to drive up to six strings of LEDs at an output

voltage up to 44V. LED dimming can be achieved with

analog dimming on the CTRL pin, and with pulse width

modulation dimming on the PWM pin. The LT3598

accurately regulates LED current even when the input

voltage is higher than the LED output voltage. The switching

frequency is programmable from 200kHz to 2.5MHz

through an external resistor.

Additional features include programmable overvoltage

protection, switching frequency synchronization to an

external clock, LED current derating based on junction

temperature and/or LED temperature, LED string disable

control, OPENLED alert pin and output voltage limiting

when all LED strings are disconnected. The LT3598 is

available in a thermally enhanced 24-lead (4mm × 4mm)

QFN and 24-lead TSSOP packages.

90% Efficient LED Driver for 60 White LEDs

Dimming Ratio

n

OPENLED Alert Pin

TSSOP Packages

LED Current Matching

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

True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the

property of their respective owners. Protected by U.S. Patents, including 7199560, 7321203.

2.61k

2.2μF

10μH

4.7μF

15nF

20mA

3598 TA01a

LT3598

FB

OPENLED

PWM

SHDN

RT

SYNC

CTRL

LED1

LED2

LED3

LED4

LED5

LED6

SW

SS

GND

1.00M

30.9k

8V TO 40V

2.2μF

5V

14.7k

10nF

47pF

100k

100k

10k

51.1k

100k

60.4k

PWM

SHDN

SYNC

TEMPERATURE (°C)

–50

0.5

1.0

0

–0.5

050

–25

25

75

100

125

–1.0

–1.5

1.5

3598 TA01b

ALL SIX LED STRINGS