Patent · US Expired

Integrable high-Q tunable capacitor and method

US5994985A · kind A · utility

26Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 5, 1997
Grant dateNov 30, 1999
Priority date
Expiry dateDec 5, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03J2200/10
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A high-performance integrable tunable inductor includes a "primary" coil and a "drive" coil placed in close proximity to each other and simultaneously driven with primary and drive currents, respectively. The drive current induces mutual components of inductance in the primary coil which vary with the phase and amplitude relationship between the two currents. These relationships are controlled to precisely establish the impedance of the primary coil, allowing the inductor to be "tuned" to provide a desired inductance or resistance by simply varying the phase and amplitude relationships appropriately. Inductance values tunable over ranges of about 2:1 and Q values of nearly 2000 have been demonstrated. The primary coil can also be made to operate as a relatively large integrated capacitance by setting the phase and amplitude relationships appropriately. The tunable inductor can be fabricated with standard CMOS processes, or any of a number of other processing technologies, and thus integrated into a host of analog circuits for which a highly-integrated implementation is desirable.

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