Patent · US Expired

Audio amplifier

US4379209A · kind A · utility

9Cited by
3References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 19, 1980
Grant dateApr 5, 1983
Priority date
Expiry dateNov 19, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F1/52
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An audio amplifier having an auxiliary terminal for connection of a feedback line to the grounded terminal of a loudspeaker and including a circuit for protection against voltage overload on the amplifier and loudspeaker if the auxiliary terminal is inadvertently connected to the ungrounded terminal of the loudspeaker, or in case of malfunction of the feedback circuit. The protection circuit includes a signal generator activated by the closing of a power switch for producing a check signal for circuiting through the terminals of the loudspeaker to the auxiliary terminal and a controller sensitive to the voltage at the auxiliary terminal for controlling a switch for disconnecting the feedback line, if the voltage at the auxiliary terminal exceeds a predetermined value.

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