LT3593

1

3593f

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

1MHz White LED Driver with

Output Disconnect and One

Pin Current Programming

The LT

drive up to ten white LEDs in series from a Li-Ion cell.

Series connection of the LEDs provides identical LED

currents and eliminates the need for ballast resistors. The

device features a unique high side LED current sense that

enables the part to function as a “one wire current source”

where the low side of the LED string can be returned to

ground anywhere.

Additional features include output disconnect in shutdown,

open LED protection and 1-pin shutdown/LED current

control. The CTRL pin is toggled to adjust the LED current

via an internal counter and a 5-bit DAC.

The LT3593 switches at 1MHz, allowing the use of tiny

external components. Constant frequency switching re-

sults in low input noise and a small output capacitor. The

LT3593 is available in the 6-lead DFN (2mm × 2mm) as

well as the 6-lead SOT-23 packages.

Li-Ion Driver for Ten White LEDs

and 6-Lead SOT-23 Packages

CTRL

10μH

3V TO 5V

3593 TA01a

LT3593

SHUTDOWN AND

CURRENT CONTROL

SW

CAP

LED

GND

1μF

1μF

Conversion Efficiency

LED CURRENT (mA)

0

90

70

50

80

60

40

30

10

3593 TA01b

20

15

5

10 LEDs

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

All other trademarks are the property of their respective owners.