Dimming control of electronic ballasts
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Nov 26, 2002
Grant Date -
Feb 7, 2002
app pub date -
Oct 13, 1998
filing date -
Oct 13, 1998
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
The invention provides an apparatus and a method for controlling the power output of a fluorescent lamp in order to provide dimming control. The fluorescent lamp is driven by an electronic ballast, for example a half-bridge resonant inverter, and the electronic ballast is switched at a constant frequency and with a constant duty-cycle, but with a variable DC voltage power input. Dimming control is provided by variation of the DC voltage power supply. The variable DC supply may be obtained from an AC source followed by a power factor corrected AC-DC variable converter, or a DC source followed by a variable DC--DC converter.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Advertisement
Advertisement
Advertisement
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully