LT3518

1

3518fb

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

Full-Featured LED Driver

with 2.3A Switch Current

internal 2.3A, 45V switch specifically designed to drive

LEDs. The LT3518 operates as a LED driver in boost, buck

mode and buck-boost mode. It combines a traditional

voltage loop and a unique current loop to operate as a

constant-current source or constant-voltage source. Pro-

grammable switching frequency allows optimization of the

external components for efficiency or component size. The

switching frequency of the LT3518 can be synchronized

to an external clock signal. The LED current is externally

programmable with a 100mV sense resistor. The external

PWM input provides 3000:1 LED dimming. The CTRL pin

provides further 10:1 dimming ratio.

The LT3518 is available in the tiny footprint 16-Lead QFN

(4mm

×4mm)andthe16-PinTSSOPpackage.TheLT3518

provides a complete solution for both constant-voltage

and constant-current applications.

Operation from 3V to 30V

Transient Protection to 40V

× 4mm) 16-Lead QFN and 16-Pin

TSSOP Packages

1.5A Buck Mode LED Driver

Efficiency

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

PWM is a trademark of Linear Technology Corporation. Patent Pending. All other trademarks are

the property of their respective owners. *Patents Pending.

1.5A

10μF

15μH

2.2μF

0.1μF

68mΩ

M1

2.2μF

ISP

TGEN

GND

16.9k

1MHz

3518 TA01a

0.1μF

SHDN

CTRL

PWM

SYNC

FB

SS

SW

24V

3.3V

ISN

LT3518

TG

PWM

PWM DUTY CYCLE (%)

0

40

50

60

70

80

90

100

20

40

60

80

3518 TA01b

100