ft2820

ft2820 4W Dual-PumpTM Class-G Audio Power Amplifier GENERAL DESCRIPTION The ft2820 is a 4W boosted Class-G audio power amplifier based upon a proprietary Dual-PumpTM topology with automatic level control (ALC). It operates from 3V to 5.5V supply. When operating with a 4.2V supply voltage, it is capable of driving a 4Ω speaker load at a continuous average output of 4W with 10% THD+N. Its high efficiency, up to 82%, helps extend battery life for portable device applications. In ft2820, the power supply rail for the amplifier’s output stage is internally boosted and regulated at 6V by an adaptive charge pump based upon the Dual-PumpTM topology, thus allowing for a much louder audio output than a stand-alone one directly connected to the battery. It makes ft2820 an ideal audio solution for portable devices that are powered by a single-cell lithium battery while requiring higher audio loudness. The ft2820 features ALC on the audio output signals, which detects the output clipping caused by the over-level input signal and automatically adjusts the voltage gain of the amplifier to eliminate the clipping while maintaining the maximally-allowed dynamic range of the audio output signals. The ALC also eliminates the output clipping due to low battery supply voltage. FEATURES  Proprietary Dual-PumpTM topology  Filterless Class-G operation with an integrated charge pump  Automatic level control to eliminate output clipping  Integrated lowpass filter for out-of-band noise rejection ...