Patents by Inventor Kohzoh Itoh
Kohzoh Itoh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 8581657Abstract: A voltage divider circuit generating a divided voltage by dividing an input voltage with a predetermined voltage division ratio, and outputting the divided voltage is disclosed. The voltage divider circuit includes a first resistor circuit including multiple resistors connected in series, the resistors being connected in parallel to corresponding fuses; and a second resistor circuit including multiple resistors connected in series, the resistors being connected in parallel to corresponding fuses, the second resistor circuit being connected in series to the first resistor circuit. The divided voltage is output from the connection of the first resistor circuit and the second resistor circuit, and the fuses of the first resistor circuit and the second resistor circuit are subjected to trimming so that the combined resistance of the first resistor circuit and the second resistor circuit is constant.Type: GrantFiled: February 21, 2007Date of Patent: November 12, 2013Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7989935Abstract: A semiconductor device having a voltage regulator is disclosed that does not have an external output condenser for phase compensation. The semiconductor device includes a semiconductor chip that includes a voltage regulator, a power supply input terminal, a ground terminal, and an output terminal for outputting a produced constant voltage; and a phase compensation condenser that is connected between the output terminal and the ground terminal for phase compensation of the voltage regulator. The semiconductor chip and the phase compensation condenser are accommodated in a single package.Type: GrantFiled: September 11, 2006Date of Patent: August 2, 2011Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7903427Abstract: A semiconductor device structure includes a semiconductor substrate, a resistor layer, and a capacitor layer. The resistor layer is configured to overlie the semiconductor substrate. The resistor layer has a resistor disposed therewithin. The capacitor layer is configured to overlie the resistor layer. The capacitor layer has a capacitor disposed over and electrically connected with the resistor. Further, a semiconductor device that generates a constant output voltage from an input voltage includes a semiconductor substrate, a resistor layer, and a capacitor layer. The resistor layer is configured to overlie the semiconductor substrate. The resistor layer has a resistor disposed therewithin. The capacitor layer is configured to overlie the resistor layer. The capacitor layer has a capacitor disposed over and electrically connected with the resistor.Type: GrantFiled: February 28, 2008Date of Patent: March 8, 2011Assignee: Ricoh Company, Ltd.Inventors: Kohzoh Itoh, Kazuhiro Kawamoto
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Patent number: 7667442Abstract: A constant voltage power supply circuit is provided with a constant voltage circuit part to convert an input voltage into a predetermined constant voltage, a first excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage while maintaining an output current that is output to a predetermined maximum value if the output current is greater than or equal to the predetermined maximum value when the output voltage is a rated voltage, and a second excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage and the output current and to output a short-circuit current if the output voltage decreases to a ground voltage when the output voltage is decreased to a predetermined value by the first excessive current protection circuit part. The second excessive current protection circuit part is disabled in response to a first test signal that is active.Type: GrantFiled: August 9, 2007Date of Patent: February 23, 2010Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Publication number: 20090295462Abstract: A voltage divider circuit generating a divided voltage by dividing an input voltage with a predetermined voltage division ratio, and outputting the divided voltage is disclosed. The voltage divider circuit includes a first resistor circuit including multiple resistors connected in series, the resistors being connected in parallel to corresponding fuses; and a second resistor circuit including multiple resistors connected in series, the resistors being connected in parallel to corresponding fuses, the second resistor circuit being connected in series to the first resistor circuit. The divided voltage is output from the connection of the first resistor circuit and the second resistor circuit, and the fuses of the first resistor circuit and the second resistor circuit are subjected to trimming so that the combined resistance of the first resistor circuit and the second resistor circuit is constant.Type: ApplicationFiled: February 21, 2007Publication date: December 3, 2009Inventor: Kohzoh Itoh
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Patent number: 7548044Abstract: A constant-voltage power circuit incorporating an over-current protection circuit having a fold back current limiting capability operative through low input voltages, and being capable of arbitrarily setting current outputs. The constant-voltage power supply circuit is configured so that a voltage output with small amplitude from a differential amplifier circuit is subjected to amplitude expansion to be amplified to range fully from the ground potential approximately to the input voltage by means of an amplitude expansion circuit, which includes an inverter consisting of an NMOS transistor and a resistor, and that the voltage resulting from the amplitude expansion is subsequently input to the gate of a PMOS transistor configured to directly control an output transistor.Type: GrantFiled: January 19, 2007Date of Patent: June 16, 2009Assignee: Ricoh Company, Ltd.Inventors: Kohzoh Itoh, Shunsei Tanaka
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Patent number: 7531994Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.Type: GrantFiled: February 22, 2008Date of Patent: May 12, 2009Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7502239Abstract: A charge pump circuit is provided for generating a voltage (1+1/n) times as high as a supply voltage. The charge pump circuit eliminates the need for diodes for preventing a current from flowing back from a high potential side of capacitors to prevent a reduction in the voltage due to a forward voltage, and reduces a reactive current and latch-up when the charge pump circuit is integrated into a single IC chip. The charge pump circuit includes a fourth switching element having a substrate gate connected to a drain for preventing a current from flowing back to an input terminal from a high potential side of fly back capacitors connected in series, and a second switching element having a substrate gate connected to a drain for preventing a current from flowing back from a high potential side of a catch-up capacitor to the fly back capacitors connected in series.Type: GrantFiled: May 8, 2007Date of Patent: March 10, 2009Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7480125Abstract: A constant voltage circuit including an input terminal to receive an input voltage, an output terminal configured to output a constant voltage converted from the input voltage to a load and an overcurrent protection circuit portion to perform an overcurrent protection operation of restricting an output current from the output terminal within a threshold current and to generate and provide logic signals including information on an operation state of the overcurrent protection operation to a control device disposed outside the constant voltage circuit to control the load based on the information.Type: GrantFiled: June 26, 2006Date of Patent: January 20, 2009Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Publication number: 20080284392Abstract: A constant voltage power supply circuit is provided with a constant voltage circuit part to convert an input voltage into a predetermined constant voltage, a first excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage while maintaining an output current that is output to a predetermined maximum value if the output current is greater than or equal to the predetermined maximum value when the output voltage is a rated voltage, and a second excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage and the output current and to output a short-circuit current if the output voltage decreases to a ground voltage when the output voltage is decreased to a predetermined value by the first excessive current protection circuit part. The second excessive current protection circuit part is disabled in response to a first test signal that is active.Type: ApplicationFiled: August 9, 2007Publication date: November 20, 2008Inventor: Kohzoh Itoh
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Publication number: 20080203981Abstract: A semiconductor device structure includes a semiconductor substrate, a resistor layer, and a capacitor layer. The resistor layer is configured to overlie the semiconductor substrate. The resistor layer has a resistor disposed therewithin. The capacitor layer is configured to overlie the resistor layer. The capacitor layer has a capacitor disposed over and electrically connected with the resistor. Further, a semiconductor device that generates a constant output voltage from an input voltage includes a semiconductor substrate, a resistor layer, and a capacitor layer. The resistor layer is configured to overlie the semiconductor substrate. The resistor layer has a resistor disposed therewithin. The capacitor layer is configured to overlie the resistor layer. The capacitor layer has a capacitor disposed over and electrically connected with the resistor.Type: ApplicationFiled: February 28, 2008Publication date: August 28, 2008Inventors: Kohzoh Itoh, Kazuhiro Kawamoto
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Publication number: 20080150501Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.Type: ApplicationFiled: February 22, 2008Publication date: June 26, 2008Inventor: Kohzoh Itoh
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Patent number: 7385378Abstract: A constant-voltage circuit includes a first transistor, a first control circuit, and a second control circuit having a second transistor and a differential amplifier. The first transistor controls an output current according to a first control signal output by the first control circuit such that an output voltage is substantially equal to a predetermined voltage. The second control circuit has a response property faster than the first control circuit to a variation of the output voltage, and causes the first transistor to increase the output current for a predetermined time period, regardless of the first control signal, when the output voltage varied to an extent greater than a predetermined output voltage variation value. The second transistor controls an operation of the first transistor according to a second control signal output by the differential amplifier such that a voltage at an inverting input terminal is substantially equal to the bias voltage.Type: GrantFiled: March 13, 2007Date of Patent: June 10, 2008Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7368900Abstract: A constant voltage circuit is disclosed that includes a constant voltage generator circuit part converting an input voltage into a predetermined constant voltage in accordance with an externally input control signal and outputting the constant voltage; a first capacitor connected to the output end of the constant voltage generator circuit part; a second capacitor charging the first capacitor; and a switch circuit part controlling charging and discharging of the second capacitor in accordance with the control signal. The switch circuit part charges the second capacitor and blocks the discharging of the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to stop outputting the constant voltage by the control signal, and stops applying the input voltage to the second capacitor and charges the first capacitor when the constant voltage generator circuit part is caused to start outputting the constant voltage by the control signal.Type: GrantFiled: February 22, 2007Date of Patent: May 6, 2008Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7358709Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.Type: GrantFiled: January 29, 2007Date of Patent: April 15, 2008Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Patent number: 7348834Abstract: An integrated circuit capable of detecting or generating a reference voltage suitable to a functionality of an electronic device is disclosed. The integrated circuit includes a plurality of reference voltage generating circuits, having characteristics different from one another, and a controller, which selects one of the plurality of reference voltage generating circuits according to the functionality of the electronic device.Type: GrantFiled: November 12, 2004Date of Patent: March 25, 2008Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Publication number: 20080029846Abstract: A semiconductor device having a voltage regulator is disclosed that does not have an external output condenser for phase compensation. The semiconductor device includes a semiconductor chip that includes a voltage regulator, a power supply input terminal, a ground terminal, and an output terminal for outputting a produced constant voltage; and a phase compensation condenser that is connected between the output terminal and the ground terminal for phase compensation of the voltage regulator. The semiconductor chip and the phase compensation condenser are accommodated in a single package.Type: ApplicationFiled: September 11, 2006Publication date: February 7, 2008Inventor: Kohzoh Itoh
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Publication number: 20070297203Abstract: A charge pump circuit is provided for generating a voltage (1+1/n) times as high as a supply voltage. The charge pump circuit eliminates the need for diodes for preventing a current from flowing back from a high potential side of capacitors to prevent a reduction in the voltage due to a forward voltage, and reduces a reactive current and latch-up when the charge pump circuit is integrated into a single IC chip. The charge pump circuit includes a fourth switching element having a substrate gate connected to a drain for preventing a current from flowing back to an input terminal from a high potential side of fly back capacitors connected in series, and a second switching element having a substrate gate connected to a drain for preventing a current from flowing back from a high potential side of a catch-up capacitor to the fly back capacitors connected in series.Type: ApplicationFiled: May 8, 2007Publication date: December 27, 2007Inventor: Kohzoh Itoh
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Patent number: 7274180Abstract: A constant voltage outputting apparatus includes an input terminal, an output terminal, a control unit, a plurality of output control transistors, and a switching unit. The input terminal receives an input voltage, and the output terminal outputs an output voltage. The control unit detects the output voltage and outputs a control signal equalizing the detected output voltage with a predetermined constant voltage. Each of the plurality of output control transistors receives the control signal and controls, according to the control signal, currents flowing from the input terminal to the output terminal. The switching unit switches the plurality of output control transistors to input the control signal thereto according to a predetermined setting. A constant voltage outputting method is also described.Type: GrantFiled: February 10, 2005Date of Patent: September 25, 2007Assignee: Ricoh Company, Ltd.Inventor: Kohzoh Itoh
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Publication number: 20070210779Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.Type: ApplicationFiled: January 29, 2007Publication date: September 13, 2007Inventor: Kohzoh Itoh