Communications: electrical – Digital comparator systems
Patent
1988-06-23
1990-09-18
Shoop, Jr., William M.
Communications: electrical
Digital comparator systems
341158, 341139, H03M 700
Patent
active
049581392
ABSTRACT:
A circuit for automatically matching the gain and offset of a time-shifted digitizing channel in a data acquisition circuit which includes a reference digitizing channel, having a fixed voltage reference, and at least one time-shifted digitizing channel having components that are adjustable for gain and offset. Feedback is provided by examining the dynamic range and average value of a known input signal which is digitized, sent through the time-shifted digitizing channel and stored in memory. A microprocessor reads the stored data and, by separately varying the gain and offset parameters, computes optimal values for each parameter. Digital-to-analog converters (DAC's) allow the microprocessor to communicate with one fixed-gain variable-offset amplifier in the front end and with one fixed-gain variable-offset amplifier and one analog-to-digital converter (ADC) in each time-shifted digitizing channel. By controlling the offset of the amplifiers and the reference level of the ADC, precise matching of the gain and offset of the time-shifted digitizing channel with the gain and offset of the reference digitizing channel may be performed easily and inexpensively. The circuit may be extended to an arbitrary number of additional time-shifted digitizing channels and provides a comparatively simple, inexpensive way to automatically match the gain and offset of each time-shifted digitizing channel.
REFERENCES:
patent: 4342983 (1982-08-01), Weigand et al.
patent: 4364027 (1982-12-01), Murooka
patent: 4736189 (1988-04-01), Katsumata et al.
patent: 4755951 (1988-07-01), Hollister
patent: 4799041 (1989-01-01), Layton
National Semiconductor Linear Applications Databook, Publication 40004, Section AN-31, p. 93, 1986, National Semiconductor Corp., Santa Clara, CA.
Caldwell, J., "Digital Scope Invades Analog Domain", Electronics, Apr. 21, 1982, pp. 131-135.
Kim Helen
Nicolet Instrument Corporation
Shoop Jr. William M.
LandOfFree
Method and apparatus for automatically calibrating the gain and does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for automatically calibrating the gain and , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for automatically calibrating the gain and will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1574186