Patent · US Expired

Recirculating analog to digital converter with auto-calibrating feature

US4799041A · kind A · utility

17Cited by
9References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 6, 1986
Grant dateJan 17, 1989
Priority date
Expiry dateOct 6, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/1023
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A recirculating type analog to digital converter is disclosed which has an auto-zero mode that is introduced prior to each conversion cycle. The loop is based on an arrangement of operational amplifiers and FET switches, and further includes a comparator circuit, a reference voltage source and a microprocessor which are coupled to the loop. Also coupled to appropriate points in the loop are three time gated integrator circuits which generate analog signals which respectively compensate for offset voltages of operational amplifiers in the loop, the offset voltage of the comparator circuit which is coupled to this loop, and the gain of the loop. The compensating signals which are generated in the auto-zero mode are applied to the loop during the conversion cycle.

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