Patent · US Expired

Lamp out detection for miniature cold cathode fluorescent lamp system

US5652479A · kind A · utility

79Cited by
75References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 25, 1995
Grant dateJul 29, 1997
Priority date
Expiry dateJan 25, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A circuit for supplying power to a fluorescent lamp. A control system comprises a buck regulator for supplying a buck current, an inverter circuit for receiving the buck current and for generating a lamp voltage, a circuit for sensing a current in a fluorescent lamp, a circuit for sensing a no lamp condition, and a controller for controlling the buck regulator and the inverter. The circuit for sensing a no lamp condition monitors a voltage level at the inverter transformer. The controller is coupled to the circuit for sensing a no lamp condition. If a no lamp condition is detected, the controller responds by shutting itself down. The controller can be reactivated by toggling an on/off signal to reset a latch.

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