Printhead substrate, printhead and printing apparatus

The present invention provides a printhead substrate capable of controlling the driving of a large number of printing elements in a reduced surface area, a printhead using the printhead substrate, and a printing apparatus using the printhead. In particular, the printhead substrate, configured so that a plurality of ink supply channels are disposed in parallel on the substrate, includes a plurality of printing element arrays composed of a plurality of printing elements disposed alongside each of the plurality of ink supply channels, a plurality of drive control circuits disposed in an area between the plurality of ink supply channels that control the driving of each of the plurality of printing element arrays, and shared wiring portions disposed in the area between the plurality of ink supply channels and shared by the plurality of drive control circuits.