Coded data generation or conversion – Analog to or from digital conversion – Digital to analog conversion
Patent
1991-04-22
1994-06-21
Logan, Sharon D.
Coded data generation or conversion
Analog to or from digital conversion
Digital to analog conversion
341139, 341127, H03M 168
Patent
active
053231597
ABSTRACT:
A D/A converter divides an input digital data into at least two overlapping digital ranges. The data in the two ranges are converted separately from digital to analog by a low-range and a high-range DAC. The resulting analog signals are then added with a weighting that maintains the proper loudness relationships in the final combined analog output. In a low range of amplitudes, only the low-range DAC performs D/A conversion. Above a predetermined amplitude threshold, some of the high significant bits to the low-range DAC are frozen, while a remaining low significant bits of the low-range DAC are permitted to vary with the input digital data. Above the predetermined amplitude threshold, a digital value is subtracted from the data fed to the high-range DAC. The subtracted value is equal to the frozen value in the low-range DAC. In some embodiments, one or more supplementary bits are developed to smooth the transition between ranges. In other embodiments, more than two DACs receive overlapping ranges of the input digital data. In some of the embodiments, positive and corresponding negative analog representations of the ranges are connected in push-pull.
REFERENCES:
patent: 3967272 (1976-07-01), Sandford, Jr.
patent: 3995266 (1976-11-01), Muller et al.
patent: 4069479 (1978-01-01), Carpenter et al.
patent: 4129864 (1978-12-01), Carpenter et al.
patent: 4410879 (1983-10-01), Gumm et al.
patent: 4430642 (1984-02-01), Weigand et al.
patent: 4450433 (1984-05-01), Moriyama
patent: 4595910 (1986-06-01), Wine
patent: 4963870 (1990-10-01), Obinata
patent: 4972188 (1990-11-01), Clement et al.
patent: 4998108 (1991-03-01), Ginthner et al.
patent: 4999628 (1991-03-01), Kakubo et al.
Imamura Akira
Obinata Hajime
Logan Sharon D.
Morrison Thomas R.
Nakamichi Corporation
LandOfFree
Digital/analog converter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Digital/analog converter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital/analog converter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2223510