Stereo Subsystem Provides Rich Audio Quality and High Output Power from a Lithium-Ion Battery

In addition to this integration, the MAX9879 employs Maxim's third-generation, ultra-low-EMI, Class D amplifier technologies to provide Class AB audio performance with Class D efficiency. It thus delivers 715mW of output power from a 3.7V supply into an 8ohm load with 88% (max) efficiency. Providing the industry's highest output power from a lithium-ion battery, the MAX9879 is ideal for cellular phones, portable media players (PMPs), and other applications that require high audio quality, output power, and efficiency.

Maxim's patented DirectDrive architecture* produces a ground-referenced output from a single supply, thus eliminating the need for large DC-blocking capacitors. To further save cost and space, the MAX9879 combines Maxim's patented Class D technologies, active-emissions limiting** and spread-spectrum modulationÝ, to significantly reduce EMI and eliminate the output filters typically required by Class D amplifiers. Additionally, the integrated low-noise, analog DPST audio switch allows users to bypass the Class D amplifier for reduction of power consumption in portable devices, thus eliminating the need for an external switch.

The MAX9879 offers best-in-class click-and-pop performance with no audible artifacts at power on/off and also high RF/TDMA noise rejection, which simplifies the design iteration process. Additional features include input mixing, volume control, comprehensive click-and-pop suppression, and a flexible, user-defined input architecture with preamplifier gain settings. All controls are enabled through an I2C interface.

The MAX9879 is packaged in a 2.5mm x 3mm, 30-bump UCSP(TM) that is fully specified over the -40 degrees Celsius to +85 degrees Celsius extended temperature range. Prices start at $1.35 (1000-up, FOB USA). An evaluation kit is available to speed designs.