Patents by Inventor Kazuki Watanabe

Kazuki Watanabe 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).

  • Publication number: 20070108301
    Abstract: In an IC card in which an internal circuit is operated by an internal power supply formed from alternate current from outside received by an antenna, the voltage of the internal power supply sometimes changes due to the operation of the internal circuit. Therefore, the voltage controlling circuit of the present invention includes a voltage controlling current source, and when the internal circuit is not operated and the current higher than a predetermined current is detected in the voltage controlling current source, an operating current detector circuit outputs an enable signal. When the internal circuit is operated in response to the enable signal, the current consumed in the internal circuit is subtracted from the current passing through the voltage controlling current source. Consequently, the current change in the entire internal power supply can be prevented, and the output voltage of the internal power supply can be kept constant.
    Type: Application
    Filed: January 9, 2007
    Publication date: May 17, 2007
    Inventors: Kazuki Watanabe, Hisataka Tsunoda, Norihisa Yamamoto, Kazuhiro Matsushita
  • Publication number: 20070097725
    Abstract: There is provided a semiconductor integrated circuit provided with a charge pump circuit of low power consumption, capable of maintaining an output voltage thereof at a predetermined voltage level without causing current consumption to undergo intermittent variation, and a contactless electronic device using the semiconductor integrated circuit. With respective charge pump circuit unit cells (charge/discharge circuits) making up the charge pump circuit, charge current/discharge current flowing to or from the capacitor, respectively, is controlled according to the output voltage of the charge pump circuit. Accordingly, the charge pump circuit can maintain the output voltage thereof at the predetermined voltage level without undergoing an intermittent action.
    Type: Application
    Filed: October 25, 2006
    Publication date: May 3, 2007
    Inventor: Kazuki Watanabe
  • Patent number: 7168624
    Abstract: In an IC card in which an internal circuit is operated by an internal power supply formed from alternate current from outside received by an antenna, the voltage of the internal power supply sometimes changes due to the operation of the internal circuit. Therefore, the voltage controlling circuit of the present invention includes a voltage controlling current source, and when the internal circuit is not operated and the current higher than a predetermined current is detected in the voltage controlling current source, an operating current detector circuit outputs an enable signal. When the internal circuit is operated in response to the enable signal, the current consumed in the internal circuit is subtracted from the current passing through the voltage controlling current source. Consequently, the current change in the entire internal power supply can be prevented, and the output voltage of the internal power supply can be kept constant.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: January 30, 2007
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kazuki Watanabe, Hisataka Tsunoda, Norihisa Yamamoto, Kazuhiro Matsushita
  • Publication number: 20060202043
    Abstract: A semiconductor integrated circuit device (IC) and a contactless IC card including a receiver circuit that is able to stably demodulate information signals superimposed on AC signals from an interrogator. The receiver circuit included in the IC is equipped with antenna terminals, a power supply circuit, and a filter circuit. The information signal from which a high frequency component was eliminated through the filter circuit is input via a capacitor to an inverting input terminal of an operational amplifier and a reference voltage is input to a non-inverting input terminal thereof. After the information signal is fed back through a feedback path to the non-inverting input terminal of the operational amplifier, that signal is amplified and the amplified information signal is binarized by a binarizing circuit, thereby data transmitted from the interrogator is demodulated. The contactless IC card comprises an antenna coil and the IC including this receiver circuit.
    Type: Application
    Filed: May 12, 2006
    Publication date: September 14, 2006
    Inventors: Kazuki Watanabe, Yutaka Nakadai, Shinichi Ozawa
  • Publication number: 20060103449
    Abstract: To augment the temperature dependence of the voltage used to detect temperature in a semiconductor integrated circuit device having a temperature detection function, the operating power supply voltage of the semiconductor integrated circuit device has needed to be enhanced. It becomes possible for such a semiconductor integrated circuit device to generate a voltage of great temperature dependence, even under a low operating power supply voltage, by including: a temperature-to-current converter which outputs a first electric current proportional to temperature; a current generator which outputs a second electric current having extremely small temperature dependence; a current subtracter which outputs a third electric current proportional to a differential current obtained by subtracting the second electric current from the first electric current; and a current-to-voltage converter which converts the third electric current into a voltage.
    Type: Application
    Filed: October 25, 2005
    Publication date: May 18, 2006
    Inventors: Kazuki Watanabe, Ryo Nemoto, Toshiaki Yazawa
  • Patent number: 7044393
    Abstract: A semiconductor integrated circuit device (IC) and a contactless IC card including a receiver circuit that is able to stably demodulate information signals superimposed on AC signals from an interrogator. The receiver circuit included in the IC is equipped with antenna terminals, a power supply circuit, and a filter circuit. The information signal from which a high frequency component was eliminated through the filter circuit is input via a capacitor to an inverting input terminal of an operational amplifier and a reference voltage is input to a non-inverting input terminal thereof. After the information signal is fed back through a feedback path to the non-inverting input terminal of the operational amplifier, that signal is amplified and the amplified information signal is binarized by a binarizing circuit, thereby data transmitted from the interrogator is demodulated. The contactless IC card comprises an antenna coil and the IC including this receiver circuit.
    Type: Grant
    Filed: January 4, 2005
    Date of Patent: May 16, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Kazuki Watanabe, Yutaka Nakadai, Shinichi Ozawa
  • Publication number: 20060076626
    Abstract: In a semiconductor integrated circuit device in which a rectifier device constituting a rectifier comprises a MOS transistor whose gate is connected to one antenna terminal and whose source is connected to the other antenna terminal, the parasitic capacitance applied between the antenna terminals increased. The present invention provides a technology for connecting a first MOS transistor whose gate is connected to a second input terminal between a first input terminal and a first output terminal, allowing an output terminal of a first bulk terminal control circuit, which is connected between the first and second input terminals, to control a bulk terminal of the first MOS transistor, and allowing an output terminal of a second bulk terminal control circuit, which is connected between the first and second input terminals, to control a bulk terminal of a second MOS transistor, which is connected between the second input terminal and the first output terminal.
    Type: Application
    Filed: October 11, 2005
    Publication date: April 13, 2006
    Inventors: Kazuki Watanabe, Yoshiki Kawajiri, Hisataka Tsunoda
  • Publication number: 20060066451
    Abstract: A measuring system enabled to simultaneously start measurement by a plurality of transponders by communication between a reader/writer and a plurality of transponders each with a built-in sensor is to be provided. In addition to an identifier SID intrinsic to a sensor and a chip identifier TID intrinsic to a transponder chip, a unique identifier UID combining the sensor SID and the chip TID is provided in each transponder. A reader/writer, in designating a transponder and transmitting a measurement command to it, invalidates the chip TID out of the UID of each transponder, validates only information regarding a sensor function, and transmits measurement commands including action commands unique to each type of sensor.
    Type: Application
    Filed: January 18, 2005
    Publication date: March 30, 2006
    Inventors: Ryo Nemoto, Tadashi Oonishi, Kazuki Watanabe, Yoshiaki Yazawa, Yasushi Goto, Hiroshi Yoshigi
  • Publication number: 20050277241
    Abstract: In an IC card in which an internal circuit is operated by an internal power supply formed from alternate current from outside received by an antenna, the voltage of the internal power supply sometimes changes due to the operation of the internal circuit. Therefore, the voltage controlling circuit of the present invention includes a voltage controlling current source, and when the internal circuit is not operated and the current higher than a predetermined current is detected in the voltage controlling current source, an operating current detector circuit outputs an enable signal. When the internal circuit is operated in response to the enable signal, the current consumed in the internal circuit is subtracted from the current passing through the voltage controlling current source. Consequently, the current change in the entire internal power supply can be prevented, and the output voltage of the internal power supply can be kept constant.
    Type: Application
    Filed: April 26, 2002
    Publication date: December 15, 2005
    Inventors: Kazuki Watanabe, Hisataka Tsunoda, Norihisa Yamamoto, Kazuhiro Matsushita
  • Patent number: 6972662
    Abstract: An RFID which provides a wide working voltage range and general versatility at low cost, without the need for changing its internal circuit design due to external factors. In the RFID, there is provided an arrangement that a low impedance state is given when its internal data communication circuit is in a reset state.
    Type: Grant
    Filed: August 15, 2000
    Date of Patent: December 6, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Takehiro Ohkawa, Miki Yuyama, Hiroshi Yoshigi, Tadashi Oonishi, Kazuki Watanabe
  • Patent number: 6955300
    Abstract: For obtaining an IC card low in both power consumption and manufacturing cost, operating conditions in case of going through a contact point, which conditions are associated with supply voltage and signal level in an internal circuit, are to lie within operating conditions in case of going through an antenna. To this end, an IC chip of the IC card is provided with a voltage conversion circuit for lowering a supply voltage supplied through the contact point and a level conversion circuit for lowering the level of a signal fed from the contact point to the internal circuit and raising the level of a signal fed from the internal circuit to the contact point.
    Type: Grant
    Filed: August 20, 2003
    Date of Patent: October 18, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Hiroshi Yoshigi, Takehiro Ookawa, Tadashi Oonishi, Kazuki Watanabe
  • Publication number: 20050173542
    Abstract: The disclosed invention provides a semiconductor integrated circuit device (IC) and a contactless IC card including a receiver circuit that is able to stably demodulate information signals superimposed on AC signals from an interrogator. The receiver circuit included in the IC is equipped with antenna terminals, a power supply circuit, and a filter circuit. The information signal from which a high frequency component was eliminated through the filter circuit is input via a capacitor to an inverting input terminal of an operational amplifier and a reference voltage is input to a non-inverting input terminal thereof. After the information signal is fed back through a feedback path to the non-inverting input terminal of the operational amplifier, that signal is amplified and the amplified information signal is binarized by a binarizing circuit, thereby data transmitted from the interrogator is demodulated. The contactless IC card comprises an antenna coil and the IC including this receiver circuit.
    Type: Application
    Filed: January 4, 2005
    Publication date: August 11, 2005
    Inventors: Kazuki Watanabe, Yutaka Nakadai, Shinichi Ozawa
  • Publication number: 20050156207
    Abstract: A wireless sensor chip suitable for the compact, high-sensitive, and low-cost examination apparatus for easily examining a biological material such as gene at low cost is provided. A sensor chip is formed on an SOI substrate, and an n type semiconductor layer on which a pMOS transistor is formed and a p type semiconductor layer on which an nMOS transistor is formed are isolated by a pn junction. Therefore, the p type semiconductor layer at the outermost portion (chip edge portion to be in contact with solution) is set to floating, and the maximum potential and the minimum potential of the chip are supplied to an n type semiconductor layer and a p type semiconductor layer inside the outermost portion, respectively. Also, the chip is covered with an ion impermeable insulating film for reducing the penetration of positive ions through the oxide layer.
    Type: Application
    Filed: September 3, 2004
    Publication date: July 21, 2005
    Inventors: Yoshiaki Yazawa, Kazuki Watanabe, Masao Kamahori, Yukinori Kunimoto
  • Publication number: 20050093302
    Abstract: A vibration-to-electric energy generator using a resonant variable capacitor (RVC) which converts vibration energy to electric energy in an environment where any kind of vibration may occur, the generator can generate electricity optimally and adaptive to change in frequency, amplitude, and phase of vibration energy. The generator includes RVC, initial charge assurance circuit, start and halt circuit, reference clock generator, pulse generation circuit, charge transportation circuit, and output control circuit. The initial charge assurance circuit and start and halt circuit control and save the conditions of electricity generating operation. The reference clock generator and pulse generation circuit generate reference signal and timing control signals in sync with vibration energy applied to the generator. By timing control signals, the charge transportation circuit charges and discharges the RVC, thus generating electric energy. The output control circuit stabilizes generated electric power.
    Type: Application
    Filed: July 20, 2004
    Publication date: May 5, 2005
    Inventors: Masayuki Miyazaki, Kazuki Watanabe, Hiroshi Toyama
  • Patent number: 6831378
    Abstract: In a semiconductor integrated circuit device and a contactless electronic device, an AC voltage is applied to first and second input terminals. A rectification transistor having a drain (or collector) connected to a second input terminal and gate (or base) and drain (or collector) connected to each other through a first resistor supplies a rectified current between the first and second input terminals. A first voltage detector means produces a control voltage so that the rectified voltage obtained on the source (or emitter) side of the first rectification transistor is equal to a predetermined reference voltage. The first voltage controlled current source can produce current in accordance with the control voltage and supply the current to the first resistor. Such a power supply circuit is mounted in the contactless electronic device.
    Type: Grant
    Filed: October 29, 2002
    Date of Patent: December 14, 2004
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kazuki Watanabe, Ryouzou Yoshino, Norihisa Yamamoto, Hajime Kinota, Keiji Kamei
  • Patent number: 6795353
    Abstract: A nonvolatile memory device and a data processing system with a reduced layout area are capable of efficiently generating a high voltage without deteriorating the charge transfer efficiency of a charge pump circuit. The charge pump circuit in a nonvolatile memory device includes a plurality of stages of charge pump unit circuits. A voltage generating unit provides, as a control signal to the gate of a first MOS transistor for transferring charges from a first capacitor of a charge pump unit circuit of one stage to a first capacitor at the next stage, a fourth signal having an amplitude of a difference voltage between the power supply voltage and the charge pump voltage of the first capacitor at the one stage. The fourth control signal is obtained from second and third signals each changing in amplitude of the power supply voltage. The second signal is supplied via a second capacitor.
    Type: Grant
    Filed: July 2, 2002
    Date of Patent: September 21, 2004
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Yuki Matsuda, Norihisa Yamamoto, Kazuhiro Matsushita, Kazuki Watanabe
  • Patent number: 6686750
    Abstract: A semiconductor integrated circuit device is provided with an IC chip so as to prevent its circuits from malfunction when the IC chip is cracked. To detect chip cracks, a resistor R01 is disposed at the outer periphery of the area in which one wants to detect the chip crack. If the chip is cracked and the resistance value of the resistor R01 is changed, the resistance change is detected, thereby controlling internal signals such as the power on reset signal and stopping the whole operation of the circuit device so as to prevent the circuits from malfunction. Thus, the system security can also be improved.
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: February 3, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kazuki Watanabe, Ryouzou Yoshino, Kenji Nagai, Tatsuya Nishihara
  • Publication number: 20030230631
    Abstract: In an IC card of dual-way type which is used in common as a non-contact/contact operation card, an isolation transistor is provided between a power supply voltage terminal and a contact power supply circuit. Non-contact/contact judging and switching unit 6 turns OFF, when it is detected that the IC card is operated in a non-contact operation mode, an isolation transistor to isolate between the power supply voltage terminal and contact power supply circuit. Accordingly, when the power supply voltage terminal is terminated with a ground terminal during the non-contact operation mode, erroneous operation of the IC card can surely be prevented. Since the power supply voltage terminal becomes equal to a reference potential in this case, monitoring of voltage of the power supply voltage terminal can be prevented and security of the IC card can also be improved remarkably.
    Type: Application
    Filed: June 2, 2003
    Publication date: December 18, 2003
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Hisataka Tsunoda, Keisuke Takata, Kazuki Watanabe, Norihisa Yamamoto, Kazuhiro Matsushita
  • Patent number: 6637664
    Abstract: For obtaining an IC card low in both power consumption and manufacturing cost, operating conditions in case of going through a contact point, which conditions are associated with supply voltage and signal level in an internal circuit, are to lie within operating conditions in case of going through an antenna. To this end, an IC chip of the IC card is provided with a voltage conversion circuit for lowering a supply voltage supplied through the contact point and a level conversion circuit for lowering the level of a signal fed from the contact point to the internal circuit and raising the level of a signal fed from the internal circuit to the contact point.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: October 28, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Yoshigi, Takehiro Ookawa, Tadashi Oonishi, Kazuki Watanabe
  • Patent number: 6585166
    Abstract: An IC card capable of preventing the occurrence of an abnormal state of coupling and thereby preventing malfunction of IC is provided. The IC card is provided with a coupling detecting means for detecting a contact coupling and a non-contact coupling and is also provided with a communication cut-off means which, when there are supplied electric power and a signal for inducing the other coupling during communication by one coupling, cuts off communication so that communication is performed by neither of the couplings.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: July 1, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Takehiro Ookawa, Hiroshi Yoshigi, Tadashi Oonishi, Kazuki Watanabe