IC Merges 24-Bit DAC With Configurable DSP

Analog Devices' latest line of digital audio processors economically eases the migration of audio processing from analog to digital. SigmaDSP ICs combine a high-performance 24-bit Δ-Σ DAC with a configurable DSP engine on the same chip.

Each chip has a 25-MIPS DSP core optimized for audio, holding a single MAC at a 25-MHz clock with a 26-bit data format and 22 bits for filter coefficients. Plus, it offers 4.0 kbytes of data memory and 3.5 kbytes of program memory. The DSP core's parameters are fully configurable via an SPI port.

The first SigmaDSP is the AD1954. Its key features—three channels of digital audio; a seven-band, 48-bit stereo equalizer; delays for loudspeaker location adjustment; Phat stereo spatial enhancement; and a dual-band, professional-quality dynamic processor—enhance speaker sound quality and eliminate high-volume distortion. Its three DACs achieve 112-dB SNR at 48-kHz sampling. The 0.5-µm CMOS-based IC consumes 400 mW (typical) in full operation at 5 V. Available in 44-pin MQFPs or 48-pin TQFPs, the AD1954 costs $5.88 in 10,000-piece quantities.

Analog Devices Inc., (781) 937-2824; www.analog.com.