U . D . White LED Driver for Backlight ■ GENERAL DESCRIPTION The NJW4603 is a high efficiency multiple strings white LED driver for back light. This device is composed with 3 channel constant current drivers and step up switching regulator, and can drive up to 24pcs. LED. Each constant current driver is able to supply maximum of 80mA per channel, and the driver interval is performed by high precision current control of ±2% typ. The NJW4603 can control luminance up to 100 : 4 by PWM signal input, and also features adjustable switching frequency of 100kHz to 1MHz. When abnormal LED lighting occurs, the FAULT terminal sends out signals notifying the abnormality to the control departments, such as CPU. The NJW4603 operates over a wide supply voltage range from 6V to 35V makes the IC ideal for medium sized LCD backlights, such as car navigations, note PC, and applications for amusement device. NJW4603 ■ PACKAGE OUTLINE NJW4603V NJW4603KT1 ■ FEATURES ▪ Constant Current Driver : 10mA ~ 80mA ▪ LED Current Control : ±2% ( typ. ) ▪ Operating Voltage : 6V ~ 35V ▪ Switching Frequency : 100kHz to 1MHz ▪ LED Open / Short Protection ▪ FAULT Signal Output ▪ Luminance Control with PWM ▪ Internal Soft Start ▪ Under Voltage Lock Out Circuit ( UVLO ) ▪ Built in Over Voltage / Over Current Protection ▪ Built in Thermal Shutdown Protection ▪ Package : NJW4603V SSOP-32 NJW4603KT1 QFN-24 Ver.2010/09/03 1 Application Power Supply 6V～35V NJW4603 CIN L1 EN CREG Regulator UVLO TSD REG Logic RT Q1 OCP FSEL PGND OSC OVP PWM PWM Input Luminance control LED Open/Short Protection LED1 SS Feedback Control EO CNF1 Current Sink LED2 LED3 Current Setting EI RNF1 FAULT (Error Flag) PGND OVP FLT CSS COUT OUT VDD Adjustable Oscillation Frequency 100kHz to 1MHz D1 Built in 40V MOS FET AGND FBO FBI ISET IGND Constant Current with Open/Short Protection RNF2 RFBI RISET Set up for LED Current 10mA to 80mA Ver.2010/09/03 2