Patent · US Active

Ballast with current control circuit

US8963447B2 · kind B2 · utility

0Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 4, 2013
Grant dateFeb 24, 2015
Priority date
Expiry dateMay 8, 2033

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B41/2825
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A ballast configured to connect to a set of lamps to energize the set of lamps is provided. The ballast comprises an inverter circuit for generating an oscillating power signal, wherein the oscillating power signal has a frequency, and a resonant tank circuit electrically connected to the inverter circuit for receiving the oscillating power signal and therefrom providing a lamp current to the set of lamps. A resistance circuit is connected to the inverter circuit. The resistance circuit has a resistance that defines the frequency of the oscillating power signal generated by the inverter circuit. A current control circuit is connected to the resistance circuit for adjusting the resistance of the resistance circuit as a function of a number of lamps that are connected to the ballast.

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