Methods for closed loop operation of capacitive accelerometers
US11249106B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 2020 |
| Grant date | Feb 15, 2022 |
| Priority date | — |
| Expiry date | Oct 28, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P2015/0814
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for closed loop operation of a capacitive accelerometer includes applying a first drive signal V1 to a first fixed capacitive electrode and a second drive signal V2 to a second fixed capacitive electrode the first and second drive signals each having a periodic waveform varying in amplitude between zero and a maximum value Vref and sensing a displacement of the proof mass and applying pulse width modulation to the first and second drive signals with a constant frequency fmod and a variable mark/space ratio. The method also includes applying a voltage offset Vref/2 to the proof mass and applying the pulse width modulation such that the first and second drive signals have a waveform that varies so that when either one of the first and second drive signals is at Vref or zero the other drive voltage is at Vref/2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.