Sept 27-07 rev G

SP7682: Backlight and Flash Driver

© 2007 Exar Corporation

Page 4

PIN DESCRIPTION

PIN #

PIN

NAME

DESCRIPTION

1

Power supply input. Place a 4.7uF decoupling capacitor next to this pin.

2

PGND

Power ground pin.

3

EN

Enable/Shutdown (Logic high = enable, logic low = shutdown). Used to immediately

disable the driver and reset the output current level.

4, 5

SCL,SDA

(SP7682)

These pins connect to the I

interface.

4

SETFL

(SP7682A)

Used to serially program the Flash LED current

5

SETBL

(SP7682A)

Used to serially program the Backlight LED’s output current

6

FLASH

High current internal current source. Connect a high brightness LED between this pin and

and 500mA with 10mA increments. During operation this pin is monitored for dropout.

When dropout condition detected the charge pump increases operation mode from 1x to

1.5x to 2x. If the FLASH current is set to above the maximum threshold the time-out

protection circuit is activated. After the maximum time of constant operation, FLASH

current is reduced to zero.

7,8,9,

10

LED1-

LED4

Internal current source for LCD backlight. Connect an LED between each of these pins

0mA and 32mA with 0.5mA increments. During operation this pin is monitored for dropout.

When dropout condition detected the charge pump increases operation mode from 1x to

1.5x to 2x. If any of the LEDs are not used connect the corresponding pin to Vout.

11

SGND

Signal ground pin.

12

VOUT

Output voltage of the internal charge pump. Connect the LEDs between this pin and the

corresponding internal current source. Connect a 2.2uF capacitor between VOUT and

PGND.

13,14,

15,16

C2+, C2-,

C1+, C1-

Connect external flying capacitors between these pins.

-

Thermal

Pad

Connect thermal pad to PGND pin.