The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Sep. 09, 2014

Filed:

Aug. 23, 2010
Applicants:

Chengming He, Shenzhen, CN;

Chingyuan Yang, Shenzhen, CH;

Inventors:

Chengming He, Shenzhen, CN;

Chingyuan Yang, Shenzhen, CH;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H05B 41/36 (2006.01); H05B 41/285 (2006.01);
U.S. Cl.
CPC ...
H05B 41/2855 (2013.01); Y02B 20/186 (2013.01);
Abstract

A backlight module detecting abnormal lamp tubes and an LCD employing such a backlight module are proposed. The LCD includes a voltage calculator for detecting voltage applied on ends of a lamp tube to monitor the lamp tube. Once the lamp tube becomes abnormal, the voltage varies accordingly. The voltage calculator calculates a voltage signal from a plurality of lamp tubes and produces a voltage value. A protection circuit regards the voltage value as a feedback signal to decide if there are any abnormalities. Once any of the lamp tubes is abnormal, the protection circuit transmits the voltage signal to a pulse-width modulated integrated circuit (PWM IC) to activate a protective function. The protection circuit of the present invention obtains the protection signal by sampling the voltage signal of the ends of the lamp tube and then gets the control signal by means of the calculation of the voltage calculator. Thus, voltage level retrieved from the protection signal are less easily affected by dimming and temperature.


Find Patent Forward Citations

Loading…