Title :
A low-cost broadcast digital audio system decoder integrated circuit
Author :
Jacobs, Gordon M.
Author_Institution :
Nuance Designworks Inc., Oakland, CA, USA
fDate :
11/1/1993 12:00:00 AM
Abstract :
The AC-1 digital audio system exploits psychoacoustic phenomena and employs Adaptive-Delta-Modulation (ADM) to achieve compression ratios of between 2.5 and 3.5:1 over 16-bit PCM. Until recently, the only practical decoder for this system consisted of a bipolar analog IC and numerous external high-precision components. This paper describes a semi-custom ASIC design for an AC-1 decoder, which combines a highly efficient 36 MIPS DSP with an oversampling D/A converter. The specifications far exceed the analog decoder, and the 8,000 gate, lμ CMOS ASIC is fabricated in a standard digital process, allowing inclusion of critical circuitry needed in a digital audio receiver as well. It exhibits a dynamic range (peak signal level to CCIR/ARM weighted idling noise) of 96 dB, yielding subjective 16-bit PCM performance at very low cost
Keywords :
CMOS integrated circuits; application specific integrated circuits; decoding; delta modulation; digital radio systems; digital signal processing chips; digital-analogue conversion; pulse-code modulation; radio broadcasting; radio receivers; 1 micron; 16 bit; 36 MIPS; AC-1 decoder; AC-1 digital audio system; CCIR/ARM weighted idling noise; CMOS ASIC; DSP; PCM; adaptive delta modulation; compression ratios; digital audio broadcast system; digital audio receiver; dynamic range; integrated circuit decoder; oversampling D/A converter; peak signal level; psychoacoustic phenomena; semicustom ASIC design; standard digital process; Analog integrated circuits; Application specific integrated circuits; Audio systems; Bipolar integrated circuits; CMOS digital integrated circuits; Decoding; Digital audio broadcasting; Digital signal processing; Phase change materials; Psychology;
Journal_Title :
Consumer Electronics, IEEE Transactions on
