A723 HIGH VOLTAGE BOOST DRIVER WITH 8 CHANNELS CONSTANT CURRENT REGULATORS www.addmtek.com DESCRIPTION FEATURES The A723 is a high voltage Boost driver with 8 channels adjustable constant current regulators for LED backlight applications. Eight regulated current ports are designed to provide uniform and pure DC constant current sinks for driving LEDs within a large range VF variations. It can drive a number of LEDs in series/parallel configuration. Users may adjust the output current from 5mA to 30mA through an external resistor, RSET, which gives users flexibility in controlling the light intensity of LEDs. It also could adjust LED brightness from 0% to 100% via PWM pin with Pulse Width Modulation signal. A feedback circuit is built in the between of Boost Driver and the Current Regulators. It could output the lowest dropout voltage among used channels to Boost Driver in order to maintain the output voltage in optimal level. An OVP circuit is built for open-loop protection when any string becomes open. The thermal protection function protects IC from over temperature damage. Also, the exposed thermal pad enhances the package power dissipation. High frequency DC/DC converter for LEDs. Integrated 50V power MOSFET. 4.5V ~ 25V wide input voltage range. 8 constant-current output channels. Output current adjustable through external resistor. Constant output current range: 5mA~30mA. 45V current sinks breakdown voltage for up to 12 pcs of LEDs in series. LED open/short protection. Green Package. APPLICATIONS Automotive interior lighting LED backlight driver for NB and Monitors. TYPICAL APPLICATION CIRCUIT VIN = 4.5V~25V PACKAGE PIN OUT CSS BYP 2 14 GND VIN 3 13 GND RT 4 12 OUT5 CVFB 5 11 OUT6 ＋ 6 7 8 9 10 OUT7 OUT8 OUT3 OUT4 RP RSET OUT2 15 OUT7 OUT6 COMP CVFB SS OUT5 OUT1 1 GND RT ISET V LED 16 OUT8 RT － 17 A723 GND A723 VIN 18 SHDN OUT4 BYP CBP 19 COMP SHDN 20 SS OUT3 OUT2 ON/OFF OUT1 PWM SW PWM SW COUT DF ISET CIN PWM VOUT L CP1 R1 R2 QFN 4mm x 4mm (Top View) ORDER INFORMATION K Green Part QFN 4mm x 4mm 20 pin A723KGT Note: The letter “G” is marked for Green parts, and letter “T” is marked for Tape & Reel. Copyright © 2009 ADDtek Corp. 1 V0.8 -- FEBRUARY 2009