MAX8822

19-0847; Rev 0; 11/07 KIT ATION EVALU LE B A IL A AV Ultra-Efficient Negative Charge-Pump LED Driver with Dual LDOs in 3mm x 3mm Thin QFN www.datasheet4u.com General Description Features ♦ High-Efficiency Charge Pump for Up to Four White LEDs Independent Adaptive Voltage Supply for Each LED 24mA to 0.1mA Dimming Range 1% (typ) Current Accuracy and 0.3% Current Matching Low 65µA (typ) Quiescent Current ♦ Dual 200mA Low-Noise, High PSRR LDOs 16 Different Output Voltage Combinations Up to 3.3V High 60dB PSRR at 10kHz ♦ Flexible Single-Wire Control for Dimming and LDO Output Voltage ♦ Low 0.5µA (typ) Shutdown Mode ♦ Soft-Start Limits Inrush Current ♦ Thermal Shutdown and Open- and Short-Circuit Protection ♦ Tiny 16-Pin, 3mm x 3mm Thin QFN Package (0.8mm max Height) with Exposed Paddle MAX8822 The MAX8822 drives up to four white light-emitting diodes (LEDs) with regulated constant current for display backlighting in cell phones, digital cameras, PDAs, and other handheld devices. By utilizing a proprietary negative 0.5x inverting charge pump and innovative independent low-dropout (LDO) adaptive current regulators, very high efficiency is achieved over the full 1-cell Li+ battery voltage range, even with large LED VF mismatch. The 1MHz fixed-frequency switching allows for tiny external components. The regulation scheme is optimized to ensure low EMI and low input ripple. Two 200mA, low-noise, high power-supply-rejection-ratio (PSRR) LDOs with programmable output voltages are i...