Precision oscillator circuit having a controllable duty cycle and related methods
US5990753A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 1997 |
| Grant date | Nov 23, 1999 |
| Priority date | — |
| Expiry date | May 30, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/0231
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A precision oscillator includes a capacitor, a charging current source, a discharging current source, a switch for alternatingly connecting the capacitor to the charging current source and the discharging current source, and a hysteretic comparator connected to the capacitor for producing an oscillating signal responsive to charging and discharging the capacitor. The oscillator may also preferably include a duty cycle controller connected to at least one of the charging current source and the discharging current source for setting the charging current and/or the discharging current to thereby set a duty cycle of the oscillating signal by setting a ratio of the charging and discharging currents. The charging current source may have a current setting input for permitting setting of a charging current to the capacitor, and the discharging current source may have a current setting input for permitting setting of a discharging current from the capacitor. The current setting inputs are connected to the duty cycle controller which, in one embodiment, may be provided by a processor and respective digital-to-analog converters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.