Maintaining constant amount of slope compensation regardless of switching frequency during synchronization
US6369665B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2000 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Oct 2, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K4/502
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An oscillator circuit that adjusts the oscillation voltage such that the voltage oscillates in a uniform manner independent of changes to frequency. Slope compensation is derived from the oscillation voltage. The adjustment is implemented by using a window comparator to establish a range of operation of the oscillation voltage. When the oscillation voltage is outside the range of operation, the window comparator instructs a counter circuit to either count up or count down, depending on the value of the oscillation voltage relative to the range. This counting then is used to adjust the amount of current which charges the capacitor. Thus, when the peak voltage is too low, the amount of current is adjusted upward. When the peak voltage is too high, the amount of current is adjusted downward. In this fashion, the oscillation voltage is maintained at a substantially uniform value, while the frequency is synchronized to an external clock signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.