The MAX9879 combines a high-efficiency stereo Class D audio power amplifier with a stereo capacitor-less DirectDrive® headphone amplifier. Maxim's filterless class D amplifiers with active emissions limiting technology provide Class AB performance with Class D efficiency.
The Class D power amplifier delivers up to 715mW from a 3.7V supply into an 8Ω load with 88% efficiency to extend battery life. The filterless modulation scheme combined with active emission limiting circuitry and spread-spectrum modulation greatly reduces EMI while eliminating the need for output filtering used in traditional Class D devices.
The headphone amplifier delivers up to 58mW from a 3.7V supply into a 16Ω load. Maxim's patented DirectDrive architecture produces a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors, saving cost, space, and component height.
The device utilizes a user-defined input architecture, three preamplifier gain settings, an input mixer, volume control, comprehensive click-and-pop suppression, and I²C control. A bypass mode feature disables the integrated Class D amplifier and utilizes an internal DPST switch to allow an external amplifier to drive the speaker that is connected at the outputs of the MAX9879.
The MAX9879 is available in a thermally efficient, space-saving 30-bump UCSP™ package.