Patent · US Expired

Electrical power control apparatus and methods

US4961047A · kind A · utility

126Cited by
5References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 24, 1989
Grant dateOct 2, 1990
Priority date
Expiry dateOct 24, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S323/911
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

Electrosurgery apparatus includes an r.f. power amplifier with an output to a patient electrode. The amplifier is controlled by the voltage of input signals from a control unit which receives a sample of the voltage and current of the output signal. The voltage and current signals are supplied to A/D converters to provide two digital signals that are used to address a look-up table in an EPROM and provide a digital output representative of impedance. A switch is set by the user to the desired mode/power curve and this provides a digital signal which together with the impedance signal is used to address a second look-up table in an EPROM which contains digital representations of the required output voltage of the amplifier to produce the desired power level. An adder compares the required voltage with a feedback of the actual voltage to produce an error signal that is supplied to the amplifier to control its output.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.