In accordance with various aspects of the present invention, a method and circuit for reducing power consumption of a power strip is provided. The inkjet head includes an ejection port substrate having ejection ports for ejection of the droplets, ejection electrodes respectively being located in a position corresponding to each of the ejection ports, and a guard electrode formed in the ejection port substrate. A pixel electrode extends from the drain electrode into the pixel area overlapping the common electrode with the gate insulating film.