Patent · US Expired

Device for reading a quantity of electric charge

US4377760A · kind A · utility

3Cited by
11References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 22, 1980
Grant dateMar 22, 1983
Priority date
Expiry dateMay 22, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R29/24
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An analog device for reading a quantity of electric charge, for example, in a transversal charge transfer filter. The device includes a capacitor and two MOS transistors which are connected in series to the point in the filter where the charge is to be read. The capacitor is connected to the common point of the two transistors which are controlled in phase opposition to insure charging of the capacitor. The capacitor maintains a potential at the charge reading point constant. Any variation in the quantity of charge under an electrode is converted into a variation of potential at the common point and this forms the read signal which is detected by means of a third MOS transistor.

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