The speaker amplifiers make use of Maxim's patented Class D architecture, providing Class AB performance with Class D efficiency, conserving board space, and extending battery life. The speaker amplifiers deliver 1.2W into an 8 load while offering efficiencies above 85%. A spread-spectrum modulation scheme reduces radiated emissions caused by the modulation frequency. Furthermore, the MAX9770/MAX9772 oscillators can be synchronized to an external clock through the SYNC input, avoiding possible problem frequencies inside a system. The speaker amplifier features THD+N as low as 0.025%, high 70dB PSRR, and SNR in excess of 90dB. The headphone amplifiers feature Maxim's patented DirectDrive architecture that produces a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors. The headphone amplifiers deliver up to 80mW into a 16 load, feature low 0.015% THD+N, high 85dB PSRR, and 8kV ESD-protected outputs. A headphone sense input detects the presence of a headphone, and automatically configures the amplifiers for either speaker or headphone mode. The MAX9770/MAX9772 include internally set, logicselectable gain, and a comprehensive input multiplexer/mixer, allowing multiple audio sources to be selected and for true mono reproduction of a stereo source in speaker mode. Industry-leading click-and-pop suppression eliminates audible transients during power and shutdown cycles. A low-power shutdown mode decreases supply current consumption to 0.1A, further extending battery life.