Differential relaxation oscillator
US4977381A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 2, 1989 |
| Grant date | Dec 11, 1990 |
| Priority date | — |
| Expiry date | Jun 2, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/0231
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A relaxation oscillator is disclosed which includes first and second currents for charging and discharging a capacitor wherein the slew rate of the dynamic voltages developed at the terminals of the capacitor remain substantially constant for each frequency of operation which desensitizes the oscillator to the effects of the inherent stray capacitance, and improves the accuracy of the output frequency. A circuit monitors the dynamic voltage across the capacitor and inverts a control signal at opposite polarities of a particular threshold. A bistable circuit provides first and second complementary output signals in response to the control signal from the circuit. The first and second complementary output signals drive a pair of switching transistors which alternate the direction of current flowing through the capacitor so as to provide smooth voltage transitions at the terminals of the capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.