Sept 27-07 rev G

SP7682: Backlight and Flash Driver

© 2007 Exar Corporation

Page 1

SP7682/SP7682A

Backlight and Flash Driver in QFN 3mm x 3mm

FEATURES

Output current up to 500mA for Flash LED

Up to 94% efficiency in 1x mode

Triple mode 1x, 1.5x and 2x charge pump

Built-in current setting DAC

SP7682 - I

SP7682A – Single Line Programmable Serial Interface

2.4MHz switching frequency

Flash LED output current adjustable in 10mA steps to 500mA

Backlight LED output current adjustable in 0.5mA steps to 31.5mA

Power-saving shutdown mode of 1μA

Time Out function to protect the LED in Flash mode (2s)

Thermal shutdown protection

Built-in over-voltage and over-current protection

Automatic soft start limits in-rush current

Lead Free, RoHS Compliant Packaging:

Space saving 16-pin 3X3mm QFN package

DESCRIPTION

The SP7682 or SP7682A provides a complete LED backlight and flash solution that is designed to drive 4 low

current LEDs for backlighting and a single channel high current output for a LED flash. The SP7682 and SP7682A

have serial interfaces that can program the backlight LED current in steps of 0.5mA up to 31.5mA and flash LED

current in steps of 10mA up to 500mA. The SP7682A uses two single line serial interfaces for programming the

backlight current and flash current. The SP7682 uses an I

standby and shutdown states, selecting flash timeout periods and switching individual LEDs for the backlight. The

data is loaded into internal registers upon power up and stored while in shutdown. When the chip is enabled, the

stored values set the LED currents. The SP7682/SP7682A automatically detects 1x, 1.5x or 2x operation for

optimal efficiency.

TYPICAL APPLICATION CIRCUIT

VIN = 2.7V to 5.5V

C1 1uF

VOUT

SDA (SETBL)

4.7uF

2.2uF

SP7682

(SP7682A)

Flash

SDA (SETBL)

FLASH

SCL (SETFL)

SCL (SETFL)

C2 1uF

LED1

LED2

LED3

LED4

EN

EN

VIN

PGND

EN

SCL (SETFL)

VOUT

SGND

LED 1

LED 2

VIN C1+

C1- C2+

C2-

PGND SGND