The MAX9702 combines a highly efficient Class D speaker amplifier with a high-linearity Class AB headphone amplifier. This ensures maximum battery life in speaker mode and maximum performance in headphone mode. The MAX9702 delivers up to 1.1W per channel into an 8 load and 1.8W into a 4 load from a 5V power supply. Maxim's 2nd-generation, spread-spectrum modulation scheme renders the traditional Class D output filter unnecessary.
The MAX9702 speaker amplifier offers two modulation schemes: a fixed-frequency (FFM) mode and a spread-spectrum (SSM) mode that reduces EMI-radiated emissions. The MAX9702 speaker amplifier features a fully differential architecture, full-bridged (BTL) output, and comprehensive click-and-pop suppression. The MAX9702 speaker amplifier features high 75dB PSRR,low 0.07% THD+N, and SNR in excess of 97dB. Short-circuit and thermal-overload protection prevent the device from being damaged during a fault condition.
The headphone amplifier uses Maxim's patented DirectDrive™ architecture that produces a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors, saving cost, board space, and component height. A high 80dB PSRR and low 0.02% THD+N ensures clean, low-distortion amplification of the audio signal.
An I²C† interface sets the speaker and headphone gain, mono, stereo, and mute functions.
The MAX9702 is available in a 28-pin thin QFN-EP (5mm x 5mm x 0.8mm) package. The MAX9702 is specified over the extended -40°C to +85°C temperature range.