Liquid ejection head and inkjet printer

An inkjet printer comprising:

• a motor configured to drive a roller for conveying a print medium;
• and
• an inkjet head configured to eject ink onto the conveyed medium and including:
• a nozzle plate including a plurality of nozzles,
• a plurality of pressure chambers, each of which is capable of storing the ink and communicates with a corresponding one of the nozzles, a volume of each pressure chamber being varied to eject the ink from the corresponding nozzle,
• a plurality of piezoelectric elements, each of which is configured to vary the volume of a corresponding one of the pressure chambers in response to a drive signal,
• an integrated circuit configured to generate the drive signal,
• a first power supply line through which a first voltage is supplied, a voltage level of the first voltage being held constant,
• a second power supply line through which a second voltage is supplied, a voltage level of the second voltage being varied and applicable to all of the piezoelectric elements,
• a first capacitor connected to the first power supply line, and
• a first switch circuit configured to selectively connect the integrated circuit to either the first or second power supply lines, wherein
• the integrated circuit generates the drive signal using either the first voltage or the second voltage supplied through one of the first and second power supply lines that is selected by the first switch circuit, and
• a capacitance of the first capacitor is no less than a total capacitance of all of the piezoelectric elements.