G5904 Global Mixed-mode Technology Inc. Four Channel High Efficiency White LED Driver Features General Description The G5904 charge pump drives up to four white LEDs with regulated constant current for uniform intensity. By utilizing dynamic 1x/2x charge-pump modes and ultra-low-dropout current regulators, it achieves high efficiency over the 1-cell lithium battery input voltage range. The 250kHz fixed frequency switching allows for tiny external components, and the regulation scheme is optimized to ensure low EMI and low input ripple. Dynamic 1x/2x Charge Pump Switching Up to 80mA (20mA/LED) Drive Capability 90% Average Efficiency 0.5% (TYP) LED Current Matching Wide Current Range per LED [0.1mA ~ 20mA] Single Wire EN/Brightness Control 2.7V to 5.5V Supply Voltage Range < 1µA Shutdown Current Output Over-voltage Protection Open/Short LED Protection Thermal Shutdown Protection TDFN2.5X2.5-10 and TQFN3X3-16 Package The G5904 uses a single wire EN/Brightness control to enable, disable, and set the LED current with 16-linear steps down to 100µA. Once the desired LED brightness is set, the G5904 maintains constant LED current as long as EN pin is kept high. If EN pin kept low for 90µs, the G5904 enters shutdown. The short-circuit, over-voltage, and thermal protection are also included. The soft start is enabled to reduce the inrush current during power on and pump mode transformed. Applications Mobile Phones White LED Backlighting Camera Flash LED Lighting Ordering Information ORDER NUMBER MARKING TEMP. RANGE PACKAGE (Green) G5904RM1U G5904R41U 5904 5904 -40°C~ +85°C -40°C~ +85°C TDFN2.5X2.5-10 TQFN3X3-16 Note: RM: TDFN2.5X2.5-10 R4: TQFN3X3-16 1: Bonding Code U: Tape & Reel EN GND 3 8 VOUT Thermal Pad LED1 4 7 LED4 LED2 5 6 LED3 TDFN2.5X2.5-10 N.C. 2 N.C. 3 N.C. 4 LED3 LED2 LED1 15 14 13 Thermal Pad C1N C1P VOUT GND 11 C1P 10 C1N 9 N.C. VIN Battery CIN 1µF LED1 LED2 LED3 LED4 High EN Low 8 9 C1 1µF 12 N.C. 2 1 7 C1P EN 6 VIN VIN 10 5 1 N.C. C1N VOUT G5904 LED4 Typical Application Circuit 16 Pin Configuration COUT 1µF GND G5904 TQFN3X3-16 TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 0.4 Jan 28, 2010 1