MAXIM Manuals

The document introduces the MAX97000 audio subsystem. The subsystem includes a mono Class D speaker amplifier and a Class H headphone amplifier, as well as an analog DPST switch. The subsystem is designed for maximum efficiency, high gain, low power consumption and low distortion. It is suitable for applications such as cell phones and portable multimedia players.

MAX9875 is a high-efficiency Class D audio power amplifier with a built-in stereo AB-class capacitor-less DirectDrive headphone amplifier. This amplifier uses Maxim's third-generation filterless Class D amplifier technology with active emissions limiting technology to provide Class AB performance with Class D efficiency. The MAX9875 can provide up to 725mW of power from a 3.7V supply to an 8Ω load with an efficiency of 87%, extending battery life. The filterless modulation scheme combined with active emissions limiting circuitry and spread-spectrum modulation greatly reduces EMI while eliminating the need for output filtering used in traditional Class D devices. The stereo AB-class headphone amplifier in the MAX9875 uses Maxim's DirectDrive architecture, which 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 uses 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.

The MAX9879 combines a high-efficiency stereo Class D audio power amplifier with a stereo capacitor-less DirectDrive® headphone amplifier. It provides Class AB performance with Class D efficiency, delivering up to 715mW of power into an 8Ω load with 88% efficiency from a 3.7V supply, extending battery life. The filterless modulation scheme, active emission limiting circuitry, and spread-spectrum modulation reduce EMI and eliminate the need for output filtering. The headphone amplifier delivers up to 58mW into a 16Ω load from a 3.7V supply. The device features a ground-referenced output, eliminating the need for large DC-blocking capacitors. It also includes a user-defined input architecture, preamplifier gain settings, input mixer, volume control, click-and-pop suppression, and I2C control. The bypass mode allows an external amplifier to drive the speaker connected to the MAX9879 outputs. The MAX9879 is available in a thermally efficient, space-saving 30-bump UCSP™ package.

The MAX9791 combines a stereo 2W Class D power amplifier, a stereo 180mW DirectDrive® headphone amplifier, and a 120mA low-dropout (LDO) linear regulator in a single device. The MAX9792 combines a mono 3W Class D power amplifier, a stereo 180mW DirectDrive headphone amplifier, and a 120mA LDO linear regulator in a single device. The MAX9791/MAX9792 feature Maxim’s DirectDrive headphone amplifier 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. High 107dB DC PSRR and low 0.006% THD+N ensure clean, low-distortion amplification of the audio signal. The ground sense feature senses and corrects for the voltage difference between the output jack ground and device signal ground. This feature minimizes headphone amplifier crosstalk by sensing the impedance in the ground return trace and correcting for it at the output jack. This feature also minimizes ground-loop noise when the output socket is used as a line out connection to other grounded equipment (for example, a PC connected to a home hi-fi system). The MAX9791/MAX9792 feature low RF susceptibility, allowing the amplifiers to successfully operate in close proximity to wireless applications. The MAX9791/MAX9792 Class D amplifiers feature Maxim’s spread-spectrum modulation and active emissions limiting circuitry. Industry-leading click-and-pop suppression eliminates audio noise and pops.

The MAX9796 combines a high-efficiency Class D, mono audio power amplifier with a mono DirectDrive™ receiver amplifier and a stereo DirectDrive headphone amplifier. Maxim’s 3rd-generation, ultra-low EMI, Class D audio power amplifiers provide Class AB performance with Class D efficiency. The MAX9796 delivers 2.3W into a 4Ω load from a 5V supply and offers efficiencies up to 80%. Active emissions limiting circuitry and spread-spectrum modulation greatly reduce EMI, eliminating the need for output filtering found in traditional Class D devices. The MAX9796 features a fully differential architecture, a full-bridged output, and comprehensive click-and-pop suppression. The device utilizes a flexible, user-defined mixer architecture that includes an input mixer, volume control, and output mixer. All controls are done through an I2C interface. The mono receiver amplifier and stereo headphone amplifier use Maxim’s DirectDrive architecture, that produces a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors, saving cost, space, and component height.

This product is a high-efficiency Class D stereo/mono audio power amplifier with a mono DirectDrive® receiver amplifier and a stereo DirectDrive headphone amplifier.

The MAX9789/MAX9790 combine a stereo, 2W Class AB speaker power amplifier with a stereo 100mW DirectDrive® headphone amplifier in a single device.

The MAX5556 is a low-cost stereo audio sigma-delta digital-to-analog converter (DAC) that provides a simple and complete stereo digital-to-analog solution for media servers, set-top boxes, video-game hardware, automotive rear-seat entertainment, and other general consumer audio applications. It features built-in digital interpolation/filtering, sigma-delta digital-to-analog conversion, and analog output filtering. The MAX5556 receives input data over a 3-wire I2S-compatible interface with left-justified audio data. Sampling rates from 2kHz to 50kHz are supported. The device operates from a single +4.75V to +5.5V analog supply with total harmonic distortion plus noise below -87dB.

MAX9850 is a low-power, high-performance stereo audio DAC with an integrated DirectDrive headphone amplifier. The MAX9850 is designed to meet the board space and performance requirements of portable devices such as cell phones and MP3 and portable DVD players. The MAX9850 uses Maxim's DirectDrive headphone technology that produces a ground-biased analog audio output from a single supply, which allows for driving the headphones directly from the amplifier outputs without large DC-blocking capacitors. This feature saves board space, provides higher click/pop suppression, and improves low-frequency (bass) response. The architecture does not require the headphone jack to be biased to a DC voltage and thus allows for a conventional, grounded chassis design. The MAX9850's flexible clocking circuitry utilizes any available system clock up to 40MHz, eliminating the need for an external PLL and multiple crystal oscillators. The DAC supports a wide range of sample rates from 8kHz to 48kHz in both master and slave modes, making the MAX9850 the easiest to use and most versatile audio DAC available. It can also be operated like traditional synchronous DACs, at any integer-oversampling ratio. The audio DAC receives input data over a flexible 3-wire interface that supports left-justified, right-justified audio data, or I2S-compatible audio data. Stereo audio line inputs are provided to either mix analog audio with the digital input stream, or to drive the headphones.

The MAX98089 is a low-power, stereo audio codec with FlexSound technology. It is ideal for portable applications due to its high performance and low power consumption. It features Class D speaker amplifiers that provide efficient amplification for two speakers. The codec enables completely filterless operation with low radiated emissions. Integrated bypass switches allow for connection to an external amplifier when the Class D amplifiers are disabled. The IC also includes a stereo Class H headphone amplifier that maximizes efficiency and outputs a ground referenced signal without the need for output coupling capacitors. It also features a mono differential amplifier that can be configured as a stereo line output. The codec supports two differential analog microphone inputs and two PDM digital microphones. Integrated switches allow for an additional microphone input and routing of microphone signals to external devices. It can also be connected to FM radios or other sources with two flexible single-ended or differential line inputs.

The MAX98088 is a full-featured audio codec whose high performance and low power consumption make it ideal for portable applications.

MAX9888 is a high performance, low power consumption audio CODEC produced by Maxim. The device supports two-way stereo audio output and two-way speaker drive. It also integrates low-pass filter, headphone amplifier, digital microphone interface, FM radio interface and other functions. It is suitable for portable audio devices.

The MAX9880A is a high-performance stereo audio codec designed for portable consumer applications such as smartphones and tablets. It operates from a single 1.8V supply to ensure low power consumption and offers a variety of input and output configurations for design flexibility.

The MAX9867 is an ultra-low power stereo audio codec designed for portable consumer devices such as mobile phones and portable gaming consoles. The device features stereo differential microphone inputs that can be connected to either analog or digital microphones. The single-ended line inputs, with configurable preamplifier, can be sent to the ADC for record or routed directly to the headphone amplifier for playback. An auxiliary ADC path can be used to track any DC voltage. The stereo headphone amplifiers support differential, single-ended, and capacitorless output configurations. Using the capacitorless output configuration, the device can output 10mW into 32Ω headphones. Comprehensive click-and-pop circuitry suppresses audible clicks and pops during volume changes and startup or shutdown. Utilizing Maxim’s proprietary digital circuitry, the device can accept any available 10MHz to 60MHz system clock. This architecture eliminates the need for an external PLL and multiple crystal oscillators. The stereo ADC and DAC paths provide user-configurable voice-band or audioband digital filters. Voiceband filters provide extra attenuation at the GSM packet frequency and greater than 70dB stopband attenuation at fS/2. The MAX9867 operates from a single 1.8V supply, and supports a 1.65V to 3.6V logic level. An I2C 2-wire seri- al interface provides control for volume levels, signal mixing, and general operating modes. The MAX9867 is available in a tiny 2.2mm 24-lead QFN package, suitable for applications with the most minimal space constraints.