Patent · US Expired

Isolator circuit for use with frequency sensitive switching circuit

US4190790A · kind A · utility

7Cited by
4References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1978
Grant dateFeb 26, 1980
Priority date
Expiry dateDec 29, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B41/392
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An isolator circuit for use with a switching circuit for energizing a ballasted load in response to a control signal of preselected frequency superimposed on AC power circuits which supply the load. In the switching circuit, a triac is gated to conduct the AC power to the load by a circuit including an impedance element and a series resonant LC network tuned to the frequency of the control signal. The control signal may be one of a plurality of control signals having different frequencies superimposed on the power circuits. The isolator circuit is connected between the traic and the load and comprises a plurality of series connected parallel resonant LC circuits each tuned to block a respective one of the control signals. A series choke blocks spurious signal voltages.

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