The MAX9773 3rd-generation, ultra-low EMI, stereo, Class D audio power amplifier provides Class AB performance with Class D efficiency. The MAX9773 delivers 1.8W per channel into a 4Ω load, and offers efficiencies above 90%. Active emissions limiting (AEL) circuitry greatly reduces EMI by actively controlling the output FET gate transitions under all possible transient conditions. AEL controls high-frequency emissions resulting from conventional Class D free-wheeling behavior in the presence of an inductive load. Zero-dead- time (ZDT) technology maintains state-of-the-art efficiency and THD+N performance by allowing the output FETs to switch simultaneously without cross conduction. A spread-spectrum modulation scheme eliminates the need for output filtering found in traditional Class D devices. These design concepts reduce component count and extend battery life. The MAX9773 offers two modulation schemes: a fixed-frequency (FFM) mode, and a spread-spectrum (SSM) mode that reduces EMI-radiated emissions. The MAX9773 oscillator can be synchronized to an external clock through the SYNC input, allowing synchronization of multiple Maxim Class D amplifiers. The sync output (SYNCOUT) can be used for a master-slave application where more channels are required. The MAX9773 features a fully differential architecture, a full bridge-tied load (BTL) output, and comprehensive click-and-pop suppression. The device features internally set gains of 12dB, 15.6dB, 20dB, and 26dB selected through two gain-select inputs, further reducing external component count. The MAX9773 features high 80dB PSRR, less than 0.1% THD+N, and SNR in excess of 88dB. Short-circuit and thermal-overload protection prevent the device from being damaged during a fault condition. The MAX9773 is available in 24-pin thin QFN-EP (4mm x 4mm x 0.8mm), and 20-bump UCSP™ (2mm x 2.5mm x 0.6mm) packages. The MAX9773 is specified over the extended -40°C to +85°C temperature range. Applications * Cellular/Multimedia Phones * Handheld Gaming Consoles * MP3 Players * Notebooks * Filterless Amplifier Passes FCC-Radiation Emissions Standards with 6in of Cable * Unique Spread-Spectrum Mode and Active Emissions Limiting Achieves Better than 15dB Margin Under FCC Limit * Zero Dead Time (ZDT) H-Bridge Maintains Good THD+N Performance * Single-Supply Operation (2.5V to 5.5V) * Stereo Output (4Ω, VDD = 5V, THD+N = 1%, POUT = 1.8W) * No LC Output Filter Required * 85% Efficiency (RL = 8Ω, POUT = 600mW) * Less Than 0.1% THD+N * High 80dB PSRR * Fully Differential Inputs * Integrated Click-and-Pop Suppression * Low-Power Shutdown Mode (0.1µA) * Short-Circuit and Thermal-Overload Protection * Pin-for-Pin Compatible with the MAX9701 * Available in Thermally Efficient, Space-Saving Packages * 24-Pin TQFN-EP (4mm x 4mm x 0.8mm) * 20-Bump UCSP (2mm x 2.5mm x 0.6mm)