US 7,321,200 B2
Square wave drive system
George C. Henry, Simi Valley, Calif. (US)
Assigned to Microsemi Corporation, Irvine, Calif. (US)
Filed on Sep. 30, 2005, as Appl. No. 11/240,115.
Application 11/240115 is a continuation of application No. 10/463280, filed on Jun. 17, 2003, granted, now 6,969,958.
Claims priority of provisional application 60/392333, filed on Jun. 27, 2002.
Claims priority of provisional application 60/389618, filed on Jun. 18, 2002.
Prior Publication US 2006/0022612 A1, Feb. 02, 2006
This patent is subject to a terminal disclaimer.
Int. Cl. H05B 37/02 (2006.01)
U.S. Cl. 315—219  [315/291; 315/307; 315/DIG. 7] 18 Claims
OG exemplary drawing
 
1. A lamp inverter comprising:
a pulse width modulation controller configured to output driving signals;
a first semiconductor switch and a second semiconductor switch, wherein the first and second semiconductor switches are coupled to the pulse width modulation controller to receive the driving signals;
a transformer having a primary winding and a secondary winding, the primary winding being coupled to the first and second semiconductor switches, the transformer being configured to produce a substantially square wave voltage at the secondary winding; and
a fluorescent lamp coupled to receive the substantially square wave voltage from the secondary winding, wherein the secondary winding has a first terminal and a second terminal, and the first terminal is directly coupled through a direct current blocking capacitor to the fluorescent lamp.