Patent · US Active

Sigma-delta analog-to-digital converter

US9372168B2 · kind B2 · utility

1Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 16, 2015
Grant dateJun 21, 2016
Priority date
Expiry dateApr 16, 2035

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05F3/02
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A potentiostat includes a voltage regulator, a current mirror, a capacitor, a comparator, a current source, and a counter. The voltage regulator maintains a voltage on a working electrode of an electrochemical sensor. The current mirror develops a mirror current that mirrors an input current from the working electrode. The capacitor is alternately charged by the mirror current, causing the capacitor voltage to increase at a rate related to the current's magnitude, and discharged by a control current, causing the capacitor voltage to decrease. The comparator outputs a waveform that includes upward and downward transitions based on the variations of the capacitor voltage. The current source produces the control current based on the waveform. The counter counts the number of upward or downward transitions in the waveform during a predetermined sampling period to produce a digital output. The digital output is representative of the magnitude of the input current.

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