Patent · US Expired

Amplifying circuit with power supply switching circuit

US5834977A · kind A · utility

40Cited by
3References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 1996
Grant dateNov 10, 1998
Priority date
Expiry dateOct 30, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F1/0238
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An amplifying circuit according to the present invention has an amplifying unit for amplifying an input signal to produce an amplified signal, a battery for generating a constant voltage (a first voltage), a step-up converter for always generating an increased voltage (or a second voltage) by increasing the constant voltage, and a selection changing circuit for supplying the increased voltage to the amplifying unit as an electric source voltage when a level of the amplified signal is higher than the constant voltage and supplying the constant voltage to the amplifying unit as the electric source voltage when a level of the amplified signal is lower than the constant voltage. Therefore, because the electric source voltage supplied to the amplifying unit is changed according to the level of the amplified signal, a loss occurring in an electric power consumed in the amplifying unit can be reduced. Also, because the increased voltage is always generated by the step-up converter as compared with a prior art in which any increased voltage is not always generated, even though the increased signal is a high frequency signal, the electric source voltage can reliably change with the level of…

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