Patent ID: 11919297
Assignee: SEIKO EPSON CORPORATION
Field: Textile and paper machines (Mechanical engineering)
Classification: CPC B | IPC B

Claim 6:
7. A liquid ejecting apparatus, comprising:
an ejection portion configured to eject liquid; and
a driving circuit configured to output a driving signal for driving the ejection portion, wherein
the driving circuit includes
a modulation circuit configured to modulate a base driving signal that is a base of the driving signal and output a modulation signal,
an amplification circuit configured to output, from a first output point, an amplified modulation signal obtained by amplifying the modulation signal,
a level shift circuit configured to output, from a second output point, a level-shift amplified modulation signal obtained by shifting a potential of the amplified modulation signal, and
a demodulation circuit configured to demodulate the level-shift amplified modulation signal and output the driving signal,

the amplification circuit includes a first gate driver that outputs, based on the modulation signal, a first gate signal and a second gate signal, a first transistor that has one end electrically coupled to the first output point and that operates based on the first gate signal, and a second transistor that has one end electrically coupled to the first output point and that operates based on the second gate signal,
the level shift circuit includes a second gate driver that outputs, based on the base driving signal, a third gate signal and a fourth gate signal, a third transistor that has one end electrically coupled to the second output point and the other end to which a signal based on the amplified modulation signal is supplied and that operates based on the third gate signal, a fourth transistor that has one end electrically coupled to the second output point and the other end to which a first power source voltage is supplied and that operates based on the fourth gate signal, and a first capacitance element that has one end to which a signal based on the amplified modulation signal is supplied and the other end electrically coupled to the other end of the fourth transistor,
the level shift circuit has a first mode in which a reference potential of the amplified modulation signal is determined as a first potential and a second mode in which a reference potential of the amplified modulation signal is determined as a second potential higher than the first potential, and
when the level shift circuit enters the second mode from the first mode,
the second gate driver outputs the third gate signal for controlling the third transistor to be nonconductive and the fourth gate signal for controlling the fourth transistor to be conductive, then outputs the third gate signal for controlling the third transistor to be conductive and the fourth gate signal for controlling the fourth transistor to be nonconductive, and thereafter outputs the third gate signal for controlling the third transistor to be nonconductive and the fourth gate signal for controlling the fourth transistor to be conductive.