Pulse detection and conditioning circuit
US5514977A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1994 |
| Grant date | May 7, 1996 |
| Priority date | — |
| Expiry date | Jun 3, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/37527
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A pulse detection and conditioning circuit senses and conditions commutation pulses produced by a DC permanent magnet motor to determine motor position. The pulses are sensed using a resistor coupled in series with the motor, so that motor current and the included pulses are continuously sensed, even during motor braking. The serially coupled resistor also provides for sensing and conditioning of pulses of both polarities produced by bi-directional operation of the motor. The pulse detecting and conditioning is performed by circuitry which performs amplitude qualification as well as frequency filtering to effectively detect valid commutation pulses to the exclusion of noise and other unwanted signals. Capacitors coupled to the motor and internal capacitors provide the frequency filtering, while the amplitude qualification is provided by a balanced differential gain stage coupled through an adjustable differential gain stage with adjustable gain to a unity gain comparator. The adjustable gain of the adjustable differential gain stage and a variable reference voltage within the unity gain comparator provide for adjustable amplitude qualification. A differential to single ended conver…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.