Abstract: A radio communication terminal of one example of the present invention is a radio communication terminal provided with an electronic device shielded to prevent electromagnetic interference, in a housing, and comprises an integrated circuit, a first resonant circuit for making non-contact communication with an external device, and a second resonant circuit resonating with the first resonant circuit.

Abstract: A radio communication terminal of one example of the present invention is a radio communication terminal provided with an electronic device shielded to prevent electromagnetic interference, in a housing, and comprises an integrated circuit, a first resonant circuit for making non-contact communication with an external device, and a second resonant circuit resonating with the first resonant circuit.

Abstract: A radio communication terminal of one example of the present invention is a radio communication terminal provided with an electronic device shielded to prevent electromagnetic interference, in a housing, and comprises an integrated circuit, a first resonant circuit for making non-contact communication with an external device, and a second resonant circuit resonating with the first resonant circuit.

Abstract: A surge absorption apparatus including a common constant voltage element having a first terminal and a second terminal, and a plurality of independent constant voltage elements each having a first terminal and a second terminal, the second terminals of the independent constant voltage elements being commonly connected to the second terminal of the common constant voltage element. The common constant voltage element and the independent constant voltage elements comprise constant voltage element diodes, respectively, and the first terminals of the common constant voltage element and the independent constant voltage elements are anodes while the second terminals of the common constant voltage element and the independent constant voltage elements are cathodes.

Abstract: A portable memory medium comprises a common connection terminal and a plurality of independent connection terminals to be electrically connected to an external apparatus, and a constant voltage semiconductor chip connected to the common connection terminal and the independent connection terminals. The constant voltage semiconductor chip includes a common constant voltage element having a first terminal connected to the common connection terminal and a second terminal which is different from the first terminal, and a plurality of independent constant voltage elements having first terminals connected to the independent connection terminals, respectively, and second terminals commonly connected to the second terminal of the common constant voltage element.

Abstract: A reader/writer for IC card according to the present invention is for carrying out transfer of information between the IC card by supplying an operating power to the IC card through its connection with the IC card, and it comprises a power supply circuit for supplying an operating power to the IC card, a current limiting circuit connected in series to the power supply circuit, for limiting the current that is supplied from the power supply circuit to the IC card to values below a predetermined value, an abnormality detection circuit for detecting abnormality in the supply of the operating power to the IC card, and a control circuit which supplies a first operating power from the power supply circuit to the portable recording medium via the current limiting circuit, when the IC card is first connected, and controls to supply a second operating power which is larger than the first operating power to the IC card from the power supply circuit, only when the supply of the first operating power is found normal with

Abstract: In an IC card information reading and writing apparatus, a clock oscillator (4.9 MHz) is incorporated in the apparatus. Since the high-frequency clock is not passed through a cable connected between the apparatus and an external control unit, but supplied from the clock oscillator to the IC card via a short distance, the external control unit can stably control the IC card through the long cable without generating crosstalk or reflection. The clock signal is selectively supplied to the IC card via an AND gate in response to a clock-enable signal from the external control unit or a binary logic signal supply voltage for the reading and writing apparatus.