Patent ID: 8553026

Claim:
A scan driver comprising a plurality of stages being configured to transmit a scan signal to a plurality of scan lines of a display device, wherein each of the stages comprises: a sequential switching unit for receiving the scan signal from an output terminal of a previous stage; a sequential output unit connected to an output terminal of a same stage of the stages; a concurrent switching unit; and a concurrent output unit connected to the output terminal, wherein the sequential switching units of the stages are configured to sequentially scan the scan signal having a first voltage in a first period, and the sequential output units of the stages are configured to sequentially output the scan signal having the first voltage, wherein the concurrent switching units of the stages are configured to concurrently output the scan signal having a same voltage in a second period, and the concurrent output units of the stages are configured to concurrently output the scan signal having the same voltage, and wherein the concurrent output unit comprises a first transistor for transmitting a second control signal to the output terminal according to a first control signal during the second period, and a gate voltage of the first transistor is controlled by a second voltage that is different from the first voltage according to the first control signal before the scan signal is changed from a first level to a second level according to the second control signal.