Patent · US Expired

Electric power supply circuit capable of reducing a loss of electric power

US4644458A · kind A · utility

219Cited by
2References
9Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMar 18, 1985
Grant dateFeb 17, 1987
Priority date
Expiry dateMar 18, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B3/44
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

In an electric power supply circuit comprising a plurality of constant current units each of which is controllable by a control voltage (V.sub.c) to keep a circuit output current (I.sub.OUT) substantially constant and which has no shunt resistor, the control voltage is supplied from a single current to voltage converter (44) operable in response to a control current (I.sub.c) corresponding to the circuit output current. A control unit (39) produces the control current in response to a detection signal supplied from a current detector (37) and representative of a result of detection of the circuit output current. A plurality of current detectors may be coupled to a plurality of control units coupled in common to the single current to voltage converter. The single current to voltage converter may be a saturable reactor, a resistor, or the like. Alternatively, each of the constant current units may comprise a shunt resistor when the shunt resistor is connected in series to a current restriction circuit coupled to an additional winding attached to the current detector.

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