Low voltage operating ring oscillator with almost constant delay time
US7391274B2 · kind B2 · utility
15Cited by
6References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 30, 2005 |
| Grant date | Jun 24, 2008 |
| Priority date | — |
| Expiry date | Aug 4, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/011
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Methods and circuits for chain ring oscillators having a constant delay time over variations of temperature and variations of semiconductor manufacturing process while requiring low operating voltage only have been disclosed. A system current source includes a constant voltage circuit generating a constant voltage and hence a constant current via a resistance element. Main parts of the constant voltage circuit are an operational amplifier and a bandgap reference circuit. Using a series of current mirrors the constant currents are mirrored to current sources contained in each of n-inverter stages of the chain ring oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.