Patent · US Expired

Inductively coupled ballast circuit

US7180248B2 · kind B2 · utility

270Cited by
150References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 22, 2004
Grant dateFeb 20, 2007
Priority date
Expiry dateMay 3, 2025

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/00
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A ballast circuit is disclosed for inductively providing power to a load. The ballast circuit includes an oscillator, a driver, a switching circuit, a resonant tank circuit and a current sensing circuit. The current sensing circuit provides a current feedback signal to the oscillator that is representative of the current in the resonant tank circuit. The current feedback signal drives the frequency of the ballast circuit causing the ballast circuit to seek resonance. The ballast circuit preferably includes a current limit circuit that is inductively coupled to the resonant tank circuit. The current limit circuit disables the ballast circuit when the current in the ballast circuit exceeds a predetermined threshold or falls outside a predetermined range.

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