Active device array substrate with protecting electrostatic discharge circuit having switching devices

An active device array substrate having protecting electrostatic discharge circuits, comprising:

• a substrate, having a peripheral circuit region and a display region;
• a pixel array disposed on the display region;
• a plurality of pads disposed on the peripheral circuit region and electrically connected to the pixel array;
• a plurality of first switching devices disposed on the peripheral circuit region and located at the outside of the pads, each of the first switching devices being electrically connected to one of the pads, wherein each of the first switching devices has a gate, a source and a drain, and the gate is electrically connected to the source and the pad;
• and
• a plurality of second switching devices disposed on the peripheral circuit region and located at the outside of the pads, each of the second switching devices being electrically connected to two adjacent first switching devices with the sources or the drains of the two adjacent first switching devices, wherein each of the second switching devices has a gate, a source and a drain, the first switching devices and the second switching devices are linearly connected to one after another, through the source of each of the second switching device electrically and directly connected to the drain of the adjacent first switching device and the drain of each of the second switching device electrically and directly connected to the source of the adjacent first switching device respectively, so as to have the protecting electrostatic discharge circuits.