Patent · US Expired

Analog to digital conversion system having automatically and dynamically variable resolution range

US5568143A · kind A · utility

9Cited by
14References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 27, 1994
Grant dateOct 22, 1996
Priority date
Expiry dateOct 27, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/18
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

In order to digitize with sufficient resolution an analog signal, which may be generated by a photodetector in a spectrophotometer, an improved analog to digital conversion system is provided having an integrator stage, an analog to digital converter, a microprocessor and interface circuits for providing communication between the microprocessor and a host computer. The integrator may include an operational amplifier with a capacitor in feedback relationship therewith for providing an output which varies linearly as function of time. The microprocessor operates the analog to digital converter to sample the integrator output at successive increments of time which increase in accordance with a binary relationship to an increment corresponding in binary value to the desired upper end of the resolution range. The digitized samples from the analog to digital converter are compared with a predetermined value in the upper end of the amplitude range of the converter. Low amplitude analog signals do not reach the predetermined level until the later sampling times and thus are resolved at the upper end of the resolution range. Higher amplitude analog signals are resolved at the lower end of t…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.