Patent · US Expired

Lamp power measurement circuit

US6624600B1 · kind B1 · utility

3Cited by
4References
22Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 13, 2002
Grant dateSep 23, 2003
Priority date
Expiry dateMar 13, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B41/3921
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A lamp power measurement circuit measures average power delivered to a gas discharge lamp. The circuit includes a voltage sensor having a first measurement output representative of AC voltage across the lamp and a current sensor having a second measurement output representative of AC current through the lamp. A first absolute value circuit is coupled in series with the first measurement output and has a first absolute value output. A second absolute value circuit is coupled in series with the second measurement output and has a second absolute value output. A pulse width modulator modulates one of the first and second absolute value outputs with the other of the first and second absolute value outputs and has a pulse width modulated output. A low-pass filter is coupled in series with the pulse width modulated output and has a DC voltage output representative of average power dissipated through the lamp.

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