Analog Devices ADAU1701 SigmaDSP 28/56-Bit Audio Processor, available now from Mouser, is a full single-chip audio system with a 28/56-bit audio DSP, ADCs, DACs, and microcontroller-like control interfaces. Signal processing comprises equalisation, cross-over, bass enhancement, delay compensation, multiband dynamics processing, speaker compensation, and stereo image widening. This processing can be used to compensate for real-world limitations of speakers, amplifiers, and listening environments, offering dramatic enhancements in perceived audio quality.
The device's signal processing is comparable to that found in high-end studio equipment. Most processing is completed in full 56-bit, double precision mode, producing very good low-level signal performance. The device is a fully programmable DSP. The easy-to-use SigmaStudio software enables the user to graphically configure a custom signal processing flow utilising blocks such as bi-quad filters, level controls, dynamics processors, and GPIO interface controls.
The device programs can be loaded on power-up either from a serial EEPROM, through its self-boot mechanism, or an external microcontroller. On power-down, the current state of the parameters can be written back to the EEPROM from the device to be recalled the next time the program is run.
Two Σ-Δ ADCs and four Σ-Δ DACs give a 98.5dB analog input to analog output dynamic. Each ADC provides a THD + N of −83dB, and each DAC has a THD + N of −90dB. Digital input and output ports enable a glueless connection to further ADCs and DACs. The device communicates through an I2C bus or a four-wire SPI port.
Typical applications include multimedia speaker systems, MP3 player speaker docks, automotive head units, mini-component stereos, digital televisions, studio monitors, speaker crossovers, musical instrument effects processors, and in-seat sound systems (aircraft/motor coaches).