Ring oscillator circuit having output with fifty percent duty cycle
US5485126A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 25, 1994 |
| Grant date | Jan 16, 1996 |
| Priority date | — |
| Expiry date | Jan 25, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B2201/02
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A ring oscillator circuit which provides an output signal having a substantially constant, fifty (50%) percent duty cycle. The circuit includes a plurality of cascaded inverting stages, each of which has an input circuit for detecting an output voltage of a preceding inverting stage. One inverting stage provides a voltage to an output node. A clamping circuit, coupled to the output node, provides current to the output node whenever the instantaneous voltage output at the output node departs from a threshold voltage of a subsequent logic circuit. The current is such as to clamp the average voltage output to the threshold voltage. The plurality of cascaded inverting stages is coupled to power supply voltage across capacitor configured transistors. The ring oscillator circuit can be employed within a voltage controlled oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.