Digitally assisted power levelling circuit for rf power generator
US5323329A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 23, 1991 |
| Grant date | Jun 21, 1994 |
| Priority date | — |
| Expiry date | Dec 23, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L5/02
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An RF generator has an analog feedback circuit in combination with a digital levelling assist circuit to compensate for non-linearities in the power metering circuit that measures the RF output energy. The digital leveling assist circuit has a digitizer with inputs coupled to receive the measured power voltage supplied from the power metering circuit and a power demand voltage. The digitizer has outputs that provide digital representations of the measured power voltage and the power demand voltage to a digital control element that derives a digital correction factor based on these digital representations. A d/a converter coupled to the digital control element provides a correction voltage corresponding to this digital correction factor, and this is furnished to a summing circuit that combines the correction voltage with the power demand voltage and with a control voltage that is supplied by the analog feedback circuit. The leveling assist circuit increases the accuracy of control of the RF output power with respect to the power demand voltage, without sacrificing the speed of the analog feedback circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.