Patent · US Expired

Monolithic accelerometer

US5345824A · kind A · utility

150Cited by
83References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 4, 1993
Grant dateSep 13, 1994
Priority date
Expiry dateMar 4, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P2015/0814
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An accelerometer comprising a microfabricated acceleration sensor and monolithically fabricated signal conditioning circuitry. The sensor comprises a differential capacitor arrangement formed by a pair of capacitors. Each capacitor has two electrodes, one of which it shares electrically in common with the other capacitor. One of the electrodes (e.g., the common electrode) is movable and one of the electrodes is stationary in response to applied acceleration. The electrodes are all formed of polysilicon members suspended above a silicon substrate. Each of the capacitors is formed of a plurality of pairs of electrode segments electrically connected in parallel and, in the case of the movable electrodes, mechanically connected to move in unison. When the substrate is accelerated, the movable electrodes move such that the capacitance of one of the capacitors increases, while that of the other capacitor decreases. The two capacitors are connected to signal conditioning circuitry which converts this differential capacitance into a corresponding voltage. Both open loop and force-balance operation are shown.

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