The MAX8678 integrates a charge pump for white light-emitting diodes (LEDs) with an audio loudspeaker amplifier. The high-efficiency, adaptive charge pump drives up to four LEDs with constant current for uniform brightness. The LED current is adjustable from 0.1mA/LED to 24mA/LED in 31 pseudo-logarithmic steps through a single-wire serial-pulse interface. High accuracy and LED-to-LED current matching are maintained throughout the adjustment range. Individual adaptive mode switching for each LED provides high efficiency with a wide range of LED forward voltages. The mono class AB audio amplifier directly drives an 8Ω loudspeaker with 1.1W RMS continuous power from a 5V supply with less than 1% THD+N. The gain is adjustable from -9dB to +18dB in ten 3dB steps through a single-wire serial-pulse interface. Clicks and pops are suppressed during on/off and all gain adjustments. Differential inputs improve common-mode noise rejection. The MAX8678 includes soft-start, thermal shutdown, open-circuit and short-circuit protection, and is available in the 16-pin, 3mm x 3mm Thin QFN package (0.8mm max height). Applications * Camera Phones * Cell Phones and Smartphones * PDAs, Digital Cameras, Camcorders * High-Efficiency White LED Charge Pump * Individual Adaptive Supply for Each LED * 4 Low-Dropout LED Current Regulators * 24mA to 0.1mA Dimming Range * Single-Wire, Serial-Pulse Dimming Interface * 1% (typ) Accuracy * Low 140µA Quiescent Current * Mono Class AB Audio Amplifier * 1.1W RMS Mono BTL Output (8Ω, VIN = 5V) * Low 0.004% THD+N at 1kHz * High 90dB PSRR at 1kHz * Fully Differential Inputs * -9dB to +18dB Gain Settings in 3dB Steps * Integrated Click/Pop Suppression * Low Quiescent Current * Soft-Start Limits Inrush Current * Thermal Shutdown, Open- and Short-Circuit Protection * 16-Pin, 3mm x 3mm Thin QFN Package