Low RF Susceptibility, Mono Audio Subsystem With DirectDrive Headphone Amplifier

The MAX9875 combines a high-efficiency Class D Audio Power Amplifier with a stereo Class AB capacitor- less DirectDrive® Headphone Amplifier Maxim’s 3rd generation, filterless Class D Amplifier with active emis- sions limiting technology provides Class AB perfor- mance with Class D efficiency. The MAX9875 delivers up to 725mW from a 3.7V supply into an 8Ω load with 87% efficiency to extend battery life. The filterless modulation scheme combined with active emissions limiting circuitry and spread-spectrum modu- lation greatly reduces EMI while eliminating the need for output filtering used in traditional Class D devices. The stereo Class AB Headphone Amplifier in the MAX9875 uses Maxim’s patented DirectDrive architec- ture, that 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. The MAX9875 is available in a thermally efficient, space-saving 20-bump WLP package. By Maxim Integrated Products