Patent ID: 7559626

Claim:
An inkjet recording head substrate having a plurality of electrothermal transducers for generating thermal energy used to discharge one color ink and a plurality of drive elements for respectively driving the plurality of electrothermal transducers mounted thereon comprising: one ink supply port; a first circuit portion which receives an input signal of a first voltage amplitude level and which outputs block selection signals and device driving signals at a second voltage amplitude level higher than the first voltage; and a second circuit portion which receives the block selection signals and the device driving signals output from the first circuit portion and which outputs control signals for controlling drive elements corresponding to electrothermal transducers to be driven, wherein the block selection signals are signals for selecting a block to be driven from a plurality of blocks each including electrothermal transducers installed with respect to the one ink supply port, wherein the device driving signals are signals for driving each of the electrothermal transducers included in the block selected by the block selection signals in accordance with image data regarding the one ink supply port, and wherein said second circuit portion comprises a NOR circuit corresponding to each of the plurality of electrothermal transducers.