SP7682AER1

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 - I2C serial interface VIN SP7682A – Single Line Programmable Serial Interface PGND 2.4MHz switching frequency Flash LED output current adjustable in 10mA steps to 500mA EN Backlight LED output current adjustable in 0.5mA steps to 31.5mA SCL (SETFL) 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 C1+ C2+ VOUT SGND LED 1 LED 2 SDA (SETBL) FLASH LED 4 LED 3 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 I2C serial interface which also allows programming active, 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 C1 1uF VIN = 2.7V to 5.5V VIN C1+ C1- C2+ CIN SDA (SETBL) SCL (SETFL) 4.7uF SDA (SETBL) SCL (SETFL) FLASH Flash C2VOUT COUT 2.2uF C2 1uF C1C2- SP7682 (SP7682A) EN EN LED1 LED2 LED3 LED4 PGND SGND Sept 27-07 rev G SP7682: Backlight and Flash Driver Page 1 © 2007 Exar Corporation ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. VCC, Enable, SCL, SDA, VFLASH, VLED..............-0.3V to 6.0V 1 Power Dissipation………………………….Internally limited Storage Temperature..……..………………-65 °C to 150 °C Junction Temperature................................-40°C to +125°C ESD @ LED pins……………...…………………+/-4kV HBM ESD all other pins………….…………………....+/-2kV HBM ELECTRICAL SPECIFICATIONS Unless otherwise specified: VIN =3.6V, CIN=4.7uF, COUT=2.2uF, CFLY=1uF, TA = -40°C to +85°C, Tj=-40°C to +125°C. Bold values apply over the full operating temperature range (-40°C to 85°C). PARAMETER Operating VIN Range Operating Input Current Quiescent Current Shutdown Supply Current ILED Voltage for DAC=000000 ILED for DAC=000001 ILED for DAC=111111 IFLASH for DAC=000001 IFLASH for DAC=110010 Current DAC Resolution Backlight Current DAC LSB Flash Current DAC LSB DAC Current Accuracy Switching Frequency Equivalent Resistance, 1x mode Equivalent Resistance, 1.5x mode Equivalent Resistance, 2x mode LEDx Pin dropout voltage FLASH Pin dropout voltage Thermal Regulation Thermal Shutdown Die Temperature Thermal Shutdown Hysteresis Over-current Protection Over-voltage protection Settle time (TS) after last count SDA, SCL, SETB, SETFL input logic low voltage SDA, SCL, SETB, SETFL input logic high voltage Turn-off time (TOFF) into shutdown Time Duration before standby, SP7682 Time Duration before standby, SP7682A Enable logic low voltage Enable logic high voltage 150 0.7 5.4 160 20 1.2 6.0 100 0.4 1.6 50 2 1 1.6 4 2 6 3 0.4 -7 1.9 2.4 1.0 10 8 0.25 0.25 0.01 170 465 MIN 2.7 2 25 0.01 0.5 31.5 10 500 6 0.5 10 7 2.9 1.8 535 1 0 34.8 TYP MAX 5.5 UNITS V mA μA μA mA mA mA mA mA Bit mA mA % MHz Ohm Ohm Ohm V V %/°C °C °C A V μs V V μs s s V V EN pin high to low TD0=TD1=0V, IFLASH>ITHRESHOLD (defined by bits TOUT0, TOUT1) IFLASH>ITHRESHOLD = 230mA Driver shutdown Driver enabled Driver turns off Driver turns on again Vout =0V Vout open To 1x mode from STANDBY mode Iout=200mA Iout=80mA Iout=500mA ILED=20mA, measure mode switching IFLASH=200mA, measure mode switching 5mA< ILED