Date: Dec 5-06 Rev E

Constant Current LED Driver

© 2006 Sipex Corporation

SP7618

Solved by

TM

The SP768 is a linear, low-side constant-current driver designed to drive high power LEDs

from an input voltage rail. The driver acts as a current source, ensuring constant LED current

for a range of input voltages. The SP768 allows implementing the lowest cost LED driver

for a variety of applications. Internal circuitry maintains the preset constant current output

for a wide voltage range at the LED input. The LED current can be adjusted up to 033mA

with an external clock applied to the CTRL pin. The built-in thermal protection automatically

stops LED current to prevent overheating. A timeout function serves as a failsafe, shutting

down the output for currents greater than 266mA after 4 seconds of continuous operation if

the enable input is not cycled. The part can be shut down by using the EN pin, or sent into

Sleep Mode holding the CTRL pin low for more than 00µS.

FEATURES

Very low dropout voltage (00mV @ A)

Accurate current regulation down to dropout

voltage

No external components

Built-in current DAC

Output current adjustable with 33.3 mA/steps

Power-saving shutdown mode of µA

Fast turn-on (<50µs)

Timeout function to protect the LED

Thermal Shutdown protection

A current capability

RoHS compliant, Lead Free packaging:

Space saving 2mmx3mm 8pin DFN

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Constant Current LED Driver

APPLICATIONS

Next Generation Mobile Phones

PDA, DSC, MP3 Players

Handheld Computers

LCD Display Modules

Keyboard Backlight

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SP7618

8 Pin DFN

8

7

6

5

1

2

3

4

GNDP

GNDP

GND

CTRL

LED

EN

LED

VCC

TYPICAL APPLICATION CIRCUIT

GENERAL DESCRIPTION