Patent · US Expired

On-chip inductor using active magnetic energy recovery

US6608361B2 · kind B2 · utility

13Cited by
6References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 2001
Grant dateAug 19, 2003
Priority date
Expiry dateNov 7, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01F17/0006
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An active inductor circuit includes a primary and a secondary coil and a drive circuit monolithically integrated on a common substrate to provide high-Q inductors. Each inductor circuit comprises a primary coil which carries a first current that varies with an RF input signal, and a secondary coil which carries a second current that varies with the RF input; an on-chip current source provides the second current. The inductor circuit is arranged such that there is a fixed phase difference of approximately 90° between the first and second currents, and such that the magnetic field induced by the second current compensates for energy that would otherwise be dissipated by the primary coil. When the second current is properly selected, the inductor circuit's input impedance is made purely imaginary, such that the circuit emulates an ideal inductor at a particular frequency.

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