Rohm Co., Ltd.

Shigemi Chimura

Yoshihiro Ikefuji

Junichi Hikita

Haruo Taguchi

Hiroharu Okada

Hiroaki Masumoto

Yoshiaki Suenaga

Toyokazu Komuro

Satoshi Yoshioka

Upon receiving an encipherment command, an enciphered authentication data generation circuit generates an enciphered authentication data based on a basic authentication data including a random number portion using an encipherment rule. The encipherment rule changes according to the number of supplied encipherment commands. A transmission circuittransmits the enciphered authentication data. A reception circuitreceives the enciphered authentication data transmitted from a second deviceA prohibition command output circuitdetermines whether the enciphered authentication data transmitted from the second devicematches with an enciphered authentication data that would be generated if the same number of encipherment commands were supplied to an enciphered authentication data generation circuit of a first deviceand outputs a prohibition command to prohibit a transmission of the data to be transmitted when the determination result is negative.

Authentication system, authentication device, authentication data producing device, and authentication method

A memory ( ) in a non contact type IC card ( ) includes a data protection region (B ) storing data requiring security and an region (B ) storing other data. A main control circuit ( ) generates data to be stored and designates a location for data storage in the region (B ) or the data protection region (B ) according to a content of the data. An address non selecting circuit ( ) selects whether the generated data is to be written into the location in the data protection region (B ) designated by the main control circuit ( ) according to a state of a state setting circuit ( ).

Non contact type IC card

In a non-contact IC card, a driving portion sequentially switches a resonance frequency of a resonance circuit . A reference voltage generating portion receives an output voltage of resonance circuit for outputting a prescribed reference voltage. An output value measuring portion measures a magnitude of the output voltage of resonance circuit at each resonance frequency using the reference voltage as a reference. An output value storing portion stores a measurement value (an output value). A manner determining portion selects the largest one of the output values stored in output value storing portion , and determines a switching manner corresponding thereto as a suitable switching manner. Thus, the suitable switching manner allowing the most efficient power supply can be achieved.

Automatic adjusting responder with no self-contained power supply

A data communication apparatus according to the present invention can be used both in one-wave mode and two-wave mode, and includes: first and second tuning circuits ( ); a power supply circuit ( ) connected to first tuning circuit ( ) for generating power by a signal received by first tuning circuit ( ); an information processing circuit ( ) connected to first tuning circuit ( ) or second tuning circuit ( ) through a switching circuit ( ) and including a detection circuit ( ), a decoder ( ), an encoder ( ) and the like. Information processing circuit ( ) includes a switch control circuit ( ) detecting if the mode of the received radio wave is one-wave mode or two-wave mode in accordance with an output from first tuning circuit ( ) and controlling switching circuit ( ) such that detection circuit ( ) is connected to one of first and second tuning circuits ( ).

Telecommunication device

A highly rigid ceramic frame ( ) is embedded in a layer of a core member ( ). An IC chip ( ) is held inside ( ) via an elastic member ( ). IC chip arranged inside ( ) will not be greatly deformed even when a strong bending, torsional, or pressing force is applied to the IC card ( ). An impact, when exerted on the IC card ( ), will not be directly conveyed to the IC chip ( ). A coil ( ) formed by printing and the like is provided at an upper end face ( ) of the ceramic frame ( ). The coil ( ) is connected to the IC chip ( ) by a wire ( ). By forming the IC chip ( ), the ceramic frame ( ) and the coil ( ) integrally in advance, the workability in fabrication is improved. Therefore, a circuit chip mounted card of high reliability and low fabrication cost can be provided.

Card mounted with circuit chip and circuit chip module

An IC card produces electric power by rectifying a high-frequency signal received from a reader/writer. A MOS transistor is connected to an antenna and the received signal is rectified by the parasitic diode of the MOS transistor. The capacitance accompanying the transistor is added to the capacitance of an input tuning capacitor. Switching the on/off state of the transistor causes the capacitance added to that of the tuning capacitor to change; accordingly, the input tuning frequency changes and the relation between the input tuning frequency and the frequency of the received high-frequency signal changes. As a result, the amplitude of the received high-frequency signal changes and thus the obtained power also changes.

Non-contact communication device

Oppositely arranged bumps ( ) are electrically connected by connecting two IC chips ( ) through an anisotropic conductor ( ) to form an IC chip module ( ). With IC chip module ( ) having such structure, two IC chips ( ) provided with functions of a processing portion and an antenna are simply stacked to provide a function for communication, and arrangement of interconnection outside IC chip ( ) is not necessary. Thus, accidental breakage of the interconnection is avoided and assembly is extremely facilitated. Therefore, a circuit chip mounted card with higher reliability and reduced manufacturing cost and the like can be provided.

Circuit chip mounted card and circuit chip module

A one-chip microcomputer according to the present invention is provided with an initial reset circuit for producing a first initial reset signal having a first reset period and a second initial reset signal having a second reset period which is longer than the first reset period, an access circuit for gaining access to an address in a nonvolatile memory such as a built-in ROM to read data therefrom, and I/O buffer circuits. A storage circuit and an I/O buffer connected to a programmable I/O terminal are provided in the I/O buffer circuit and a function of the I/O terminal with options is selected in conformity with the data set in the storage circuit. The data stored at a predetermined address in the nonvolatile memory is transferred to the storage circuit by operating the access circuit until the termination of the reset period of the second initial reset signal after the termination of the first reset period of the first initial reset signal. With this arrangement, as the contents of write data are altered by writing the data to the nonvolatile memory from the outside, an optional function of the programmable I/O terminal can be selected in accordance with the alteration.

One chip microcomputer having programmable I/O terminals programmed

The improved CMOS output circuit has an enhancement-type PMOS and an enhancement-type NMOS connected in order between a power supply line and a reference potential line and that has the junction between the PMOS and the NMOS connected to an output terminal. The PMOS is such that a P-type region is provided in the back gate region to form a diode, with the back gate region being connected to the power supply line via the diode. A switch circuit is inserted between the gate of this PMOS and said junction or the output terminal. When a voltage higher than the voltage on the power supply line is applied to the output terminal, the applied voltage will turn on the switch circuit.

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Kyoto, Japan

Shigemi Chimura