| 摘要 |
This invention is directed to: a printhead substrate which employs a constant current driving method and can suppress power consumption in a standby state, prevent an increase in printhead temperature, and stably discharge ink; a printhead using the printhead substrate; a head cartridge incorporating the printhead; and a printing apparatus using the printhead. The head substrate includes a plurality of printing elements; a plurality of driving elements which are provided in correspondence with the plurality of printing elements and drive the plurality of printing elements; a reference voltage generation circuit which generates a reference voltage; a reference current generation circuit which generates a first reference current on the basis of the generated reference voltage; a plurality of constant current sources, each of which generates a constant current to drive the plurality of printing elements on the basis of the generated first reference current; and a switch which controls supply of the first reference current in accordance with a printing operation.
|
