| US 7,612,505 B2 | ||
| Liquid crystal display backlight inverter | ||
| Byoung Own Min, Gyunggi-do (Korea, Republic of); and Jung Chul Gong, Seoul (Korea, Republic of) | ||
| Assigned to Samsung Electro-Mechanics Co., Ltd., Gyunggi-Do (Korea, Republic of) | ||
| Filed on Jun. 20, 2007, as Appl. No. 11/812,678. | ||
| Claims priority of application No. 10-2006-0055397 (KR), filed on Jun. 20, 2006. | ||
| Prior Publication US 2007/0290723 A1, Dec. 20, 2007 | ||
| Int. Cl. H05B 37/02 (2006.01) | ||
| U.S. Cl. 315—291 [315/247; 315/360; 345/87; 345/102] | 4 Claims |
| 1. A liquid crystal display backlight inverter comprising:
a dimming control unit comparing a level of a triangle wave of a first frequency with a level of a dimming control signal
and controlling a dimming control current to be supplied or interrupted according to a comparison result;
an error amplification unit having an input end to which a detection voltage corresponding to the dimming control current
and a current flowing through a lamp are inputted, comparing the detection voltage with a predetermined reference voltage,
and outputting an error voltage corresponding to a difference via an output end thereof, the output end configured to ground
when the dimming control current is not inputted;
a time constant circuit unit comprising a resistor connected between the output end of the error amplification unit and a
voltage source and a capacitor connected between the output end of the error amplification unit and a ground; and
a lamp control pulse generating unit having an input end connected to the output end of the error amplification unit, comparing
a level of a signal inputted via the input end with a level of a triangle wave having a second frequency, and generating a
lamp control pulse with a duty controlled according to a comparison result.
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