U . D . White LED Driver for Backlight ■ GENERAL DESCRIPTION The NJW4600 is a high efficiency multiple strings white LED driver for back light.This device is composed with 4channel constant current drivers and step up switching regulator, and can drive up to 32pcs. LED. Each constant current driver is able to supply maximum of 120mA per channel, and the driver interval is performed by highly precise current control of ±2% typ. The NJW4600 can control luminance up to 100 : 4 by PWM signal input, and also features selectable switching frequency of 800kHz or 1MHz. When abnormal LED lighting occurs, the FAULT terminal sends out signals notifying the abnormality to the control departments, such as CPU. The NJW4600 operates over a wide supply voltage range from 6V to 35V, and operating temperature is up to 105ºC. This very wide operating temperature range makes the IC ideal for medium sized LCD backlights, such as car navigations, note PC, and applications for amusement device. NJW4600 ■ PACKAGE OUTLINE NJW4600V NJW4600KT1 ■ FEATURE ▪ Constant Current Driver : 10mA ~ 120mA ▪ LED Current Control : ±2% ( typ. ) ▪ Operating Voltage : 6V ~ 35V ▪ Switching Frequency : 800kHz / 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 Protection ▪ Built in Over Current Protection ▪ Built in Thermal Shutdown Protection ▪ Package : NJW4600V SSOP-32 NJW4600KT1 QFN-24 Ver.2010/09/03 1 Application Power Supply 6V～35V NJW4600 L1 CIN D1 COUT Thermal Shut Down Over Current Protection Over Voltage Protection VDD Select Oscillation Frequency Low: 800kHz High:1MHz EN CREG Regulator UVLO TSD REG EXT Logic FSEL OSC PWM Input Luminance control PWM OVP FLT CSS FAULT (Error Flag) OCP CS OVP RCS LED Open/Short Protection LED1 SS LED2 Feedback Control EO CNF1 Q1 Current Sink Current Setting EI LED3 LED4 RNF1 AGND FBO FBI ISET RNF3 RFBI RISET IGND Constant Current with Open/Short Protection Set up for LED Current 10mA to120mA Ver.2010/09/03 2