Printhead board, printhead and printing apparatus
AssigneeCanon Kabushiki Kaisha
InventorsTatsuo Furukawa, Yoshiyuki Imanaka, Nobuyuki Hirayama
Life of this patent
Estimating the term…
Abstract
The gate-width ratio between an NMOS transistor (1) and PMOS transistors (2, 3) constructing an initial inverter stage of a voltage converting circuit is set in such a manner that the threshold voltage of the initial inverter becomes a voltage at which an inversion is possible, this voltage being less than one-half the power-supply voltage (VHT) of the voltage converting circuit and, moreover, less than the power-supply voltage (Vdd) of a logic circuit.
Claims21
A substrate for a printhead comprising:
- a printing element for discharging ink and printing;
- a logic circuit for outputting a logic signal for driving said printing element;
- transistors for driving said printing element by a signal based on the logic signal outputted from said logic circuit;
- and
- a voltage converting circuit, which has a plurality of inverters disposed between said logic circuit and gate electrodes of said transistors, for converting the voltage of the logic signal by utilizing a predetermined power-supply voltage,
- wherein one of said plurality of inverters, which is provided at an initial stage of said voltage converting circuit, comprises a PMOS transistor and an NMOS transistor, and a transistor structure of said PMOS transistor and said NMOS transistor is adjusted in such a manner that the threshold voltage of said initial stage inverter becomes a voltage which is less than one-half the predetermined power-supply voltage and which is less than a power-supply voltage of the logic signal outputted from said logic circuit.
A printhead comprising:
- a printing element for discharging ink and printing;
- a logic circuit for outputting a logic signal for driving said printing element;
- transistors for driving said printing element by a signal based on the logic signal outputted from said logic circuit;
- and
- a voltage converting circuit, which has a plurality of inverters disposed between said logic circuit and gate electrodes of said transistors, for converting the voltage of the logic signal by utilizing a predetermined power-supply voltage,
- wherein one of said plurality of inverters, which is provided at an initial stage of said voltage converting circuit, comprises a PMOS transistor and an NMOS transistor, and a transistor structure of said PMOS transistor and said NMOS transistor is adjusted in such a manner that the threshold voltage of said initial stage inverter becomes a voltage which is less than one-half the predetermined power-supply voltage and which is less than a power-supply voltage of the logic signal outputted from said logic circuit.
A printing apparatus equipped with a printhead having a printing element for discharging ink and printing, a logic circuit for outputting a logic signal for driving said printing element, transistors for driving said printing element by a signal based on the logic signal outputted from said logic circuit, and a voltage converting circuit, which has a plurality of inverters disposed between said logic circuit and gate electrodes of said transistors, for converting the voltage of the logic signal by utilizing a predetermined power-supply voltage, image data being printed on a printing medium while the logic signal is transferred to said printhead,
- wherein one of said plurality of inverters, which is provided at an initial stage of said voltage converting circuit, comprises a PMOS transistor and an NMOS transistor, and a transistor structure of said PMOS transistor and said NMOS transistor is adjusted in such a manner that the threshold voltage of said initial stage inverter becomes a voltage which is less than one-half the predetermined power-supply voltage and which is less than a power-supply voltage of the logic signal outputted from said logic circuit.
A substrate for a printhead comprising:
- a printing element for discharging ink and printing;
- a logic circuit for outputting a logic signal for driving said printing element;
- transistors for driving said printing element by a signal based on the logic signal outputted from said logic circuit;
- and
- a voltage converting circuit, which has a plurality of inverters disposed between said logic circuit and gate electrodes of said transistors, for converting the voltage of the logic signal by utilizing a predetermined power-supply voltage, one of said plurality of inverters, which is provided at an initial stage of said voltage converting circuit, comprising a PMOS transistor and an NMOS transistor, and a transistor structure of said PMOS transistor and said NMOS transistor being adjusted in such a manner that the threshold voltage of said initial stage inverter becomes a voltage which is less than one-half the predetermined power-supply voltage and which is less than a power-supply voltage of the logic signal outputted from said logic circuit.
A printhead comprising:
- a printing element for discharging ink and printing;
- a logic circuit for outputting a logic signal for driving said printing element;
- transistors for driving said printing element by a signal based on the logic signal outputted from said logic circuit;
- and
- a voltage converting circuit, which has a plurality of inverters disposed between said logic circuit and gate electrodes of said transistors, for converting the voltage of the logic signal by utilizing a predetermined power-supply voltage, one of said plurality of inverters, which is provided at an initial stage of said voltage converting circuit, comprising a PMOS transistor and an NMOS transistor, and a transistor structure of said PMOS transistor and said NMOS transistor being adjusted in such a manner that the threshold voltage of said initial stage inverter becomes a voltage which is less than one-half the predetermined power-supply voltage and which is less than a power-supply voltage of the logic signal outputted from said logic circuit.
A printing apparatus equipped with a printhead for printing image data on a printing medium by transferring a logic signal to said printhead, comprising:
- a printing element for discharging ink and printing;
- a logic circuit for outputting the logic signal for driving said printing element;
- transistors for driving said printing element by a signal based on the logic signal outputted from said logic circuit;
- and
- a voltage converting circuit, which has a plurality of inverters disposed between said logic circuit and gate electrodes of said transistors, for converting the voltage of the logic signal by utilizing a predetermined power-supply voltage, one of said plurality of inverters, which is provided at an initial stage of said voltage converting circuit, comprising a PMOS transistor and an NMOS transistor, and a transistor structure of said PMOS transistor and said NMOS transistor being adjusted in such a manner that the threshold voltage of said initial stage inverter becomes a voltage which is less than one-half the predetermined power-supply voltage and which is less than a power-supply voltage of the logic signal outputted from said logic circuit.
Dependencies are inferred from the claim text.