Self calibrating dual range A/D converter

Details Self calibrating dual range A/D converter Self calibrating dual range A/D converter

1991-06-12

1992-11-17

Pellinen, A. D.

Coded data generation or conversion

Converter calibration or testing

358174, H03M 110

Patent

active

051647265

ABSTRACT:
A dual range A/D converter includes a gain matching circuit for balancing the upper end of the transfer curves of the level-dependent dual A/D signal paths of the converter so as to control crossover between the paths. One path (high gain path) is provided with signal gain that is a nominal multiple of gain applied to the other path (low gain path). A digital comparator compares the digital code word output of flash A/D converters included in the respective paths, with the output from the high gain path being scaled down to correspond to the output from the low gain path. If a difference is detected, the upper ladder reference of the flash converter in the low gain path is adjusted until the respective gain difference becomes substantially an exact multiple. When this matching is combined with black level correction, which equalizes the lower end of the transfer curves, a fully self-calibrating dual range A/D converter is obtained.

REFERENCES:
patent: 4521811 (1985-06-01), Stoughton et al.
patent: 4559523 (1990-12-01), Wakita
patent: 4875048 (1990-10-01), Shimizu et al.
patent: 4896155 (1990-01-01), Craiglou
patent: 4903023 (1990-02-01), Evans et al.
patent: 4907084 (1990-03-01), Nagafusa
patent: 4908621 (1990-03-01), Polonio et al.
patent: 5053771 (1991-10-01), McDermott
Mitchell, Ray "The Marconi B3410 Line Array Telecine," SMPTE Journal, Nov. 1982, pp. 1066-1070, described in the specification on page 3, line 30.
Mitchell, Ray "Digital Video Processing for Telecine," IBC 1982, IEE Conf. Publ. N220, IEE London, U.K. pp. 41-45, Sep. 18-21, 1982 see pg. 3, line 28.
Milch, "High Resolution Digitization of Photographic Images with an Area Charge-Coupled Device (CCD) Imager," SPIE vol. 697, Appl. of Digital Image Proc. IX 1986, pp. 96-104 p. 4, line 10 (specification).
Oliphant, Andrew & Weston, Martin, "A Digital Telecine Processing Channel," SMPTE Journal, vol. 88, Jul. 1979, pp. 474-479, in the specification page 3, line 5.

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