| 摘要 |
<p>A backlight module (10) detecting abnormity of lamp tubes (22) and an LCD (20, 80) are provided. The backlight module (10, 90) includes a few of lamp tubes (22), a protective circuit (36) electrically connected to two ends of each lamp tube (22), and a driver (25). The protective circuit (36) includes a first detection circuit (50) and a second detection circuit (52) for detecting the voltage of the first and second ends of the lamp tubes (22) respectively, and a comparator (54) electrically connected to the first and second detection circuits (50, 52). The comparator (54) can produce a protective signal (56) based on the difference of the detected voltage of the first and second detection circuits (50, 52). When the lamp tube (22) is abnormal, the protective signal (56) can be beyond a predetermined value, thus the driver (25) adjusts the supply voltage for the lamp tube.</p> |
