Accurate RC oscillator having peak - to - peak voltage control
US5670915A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 1996 |
| Grant date | Sep 23, 1997 |
| Priority date | — |
| Expiry date | May 24, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/0231
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An accurate RC oscillator circuit located within a microcontroller chip for generating a signal of a predetermined frequency that accurately oscillates between two precise voltage levels, i.e., a low voltage (VL) and a high voltage (VH) is disclosed. The oscillator circuit uses first and second comparators having their outputs respectively coupled to set and reset inputs of a flip flop. The output of the flip flop is coupled to a series RC network for controlling the charging and discharging of the voltage across a capacitor of the RC network. The interconnection of the series RC network is coupled to an input of both the first and second comparators. The other input of the first comparator is coupled to a circuit for applying a modified high threshold version (VH') of the high voltage such that the signal generated by the oscillator circuit does not exceed the precise high voltage (VH). Similarly, the other input of the second comparator is coupled to a circuit for applying a modified low threshold version (VL') of the low voltage such that the signal generated by the oscillator circuit does not fall below that precise low voltage (VL). Additionally, means are provided to select d…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.