Apparatus and method for testing driving circuit in liquid crystal display
AssigneeLG. Philips LCD Co., Ltd.
InventorSeong Gyun Kim
Life of this patent
Estimating the term…
Abstract
A driving circuit testing method that can quickly perform a test of a driving circuit in a liquid crystal display and a repair of defects thereof. In the method, a test signal is applied in parallel to all a plurality of gate lines and a start signal is applied to a first gate driving cell. The start signal and the test signals on a plurality of gate lines is latched into the plurality of gate driving cells. Signals latched into the plurality of gate driving cells, instead of the test signal being applied to the plurality of gate lines, are applied to the plurality of gate lines. Then, an enable state in each gate line is detected.
Claims28
A method for testing a driving circuit of a liquid crystal display having a plurality of gate driving cells connected to a plurality of corresponding gate lines and connected in series to a start signal line, the steps comprising:
- applying a test signal to the plurality of gate lines;
- applying a start signal to a first gate driving cell in the plurality of gate driving cells;
- latching the test signal to each gate driving cell;
- replacing the test signal being applied to the plurality of gate lines with the test signals latched into the plurality of gate driving cells;
- and
- testing a signal state of each gate line.
A method for testing a driving circuit of a liquid crystal display having a plurality of gate driving cells connected to a plurality of gate lines and connected in series to a start signal line, the steps comprising:
- first step of applying a test signal to the plurality of gate lines in parallel;
- second step of applying a start signal to a first gate driving cell in the plurality of gate driving cells;
- third step of latching the test signals to any one of odd-numbered and even-numbered gate driving cells in the plurality of gate driving cells;
- fourth step of replacing the signals latched into any one of the odd-numbered and even-numbered gate driving cells with the testing signal;
- and
- fifth step of testing an enable state in each gate line connected to any one of the odd-numbered and even-numbered gate driving cells.
A driving circuit testing apparatus for a liquid crystal display having a plurality of gate driving cells connected to a plurality of gate lines and connected in series to a start signal line, the driving circuit testing apparatus comprising:
- means for applying a test signal to the plurality of gate lines;
- latching control means for latching the test signal in the plurality of gate lines to each gate driving cell;
- signal switching means for replacing the test signal being applied to the plurality of gate lines with the test signal latched in the plurality of gate driving cells;
- and
- detecting means for detecting an enable state in each gate line.
A driving circuit testing apparatus for a liquid crystal display having a plurality of gate driving cells connected to a plurality of gate lines and connected in series to a start signal line, the driving circuit testing apparatus comprising:
- means for applying a test signal to the plurality of gate lines;
- latching control means for allowing the signals on the gate lines to be latched into any one of odd-numbered and even-numbered gate driving cells in the plurality of gate driving cells;
- signal switching means for replacing the test signal latched to any one of the odd-numbered and even-numbered gate driving cells with the testing signal;
- and
- detecting means for detecting an enable state in each gate line connected to any ones of the odd-numbered and even-numbered gate driving cells.
A driving circuit tester for a liquid crystal display having a plurality of gate lines, the driving circuit test comprising:
- a first set of gate line drivers in which each gate driver is detachably connected to a corresponding gate line, wherein an output of a preceding gate line driver is connected to an input of a succeeding gate line driver;
- a second set of gate line drivers in which each gate driver is detachably connected to corresponding gate line, wherein an output of a preceding gate line driver is connected to an input of a succeeding gate line driver;
- a test signal line connected to the plurality of gate lines to provide a test signal to the plurality of gate lines;
- and
- a driver controller connected to the first and the second sets of gate line drivers, wherein an input signal of the first and the second sets of gate line drivers is outputted as an output signal in response to a driver control signal from the latch controller.
Dependencies are inferred from the claim text.