Patent · US Expired

Switched reactance modulated E-class oscillator design

US6889087B2 · kind B2 · utility

9Cited by
56References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 26, 2002
Grant dateMay 3, 2005
Priority date
Expiry dateSep 9, 2023

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61N1/3727
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A modulated Class E transmitter is disclosed. In one embodiment of the invention, the modulated Class E oscillator achieves high coil currents (˜1 A) and voltages (˜500V) with low power components by precisely timed injection of current when the oscillating current in the inductor passes through zero. A detector circuit is used to trigger the current injection at the appropriate instant regardless of changes in the resonant frequency of the system. Its phase can be adjusted to compensate for propagation delays in the drive circuitry, while amplitude modulation is accomplished by switching in additional reactive conductance to increase the current injected into the tank circuit. Frequency modulation is accomplished in an alternate embodiment.

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