| 摘要 |
PROBLEM TO BE SOLVED: To provide a terminal used for input/output which is made to function as an output terminal in a normal state where anything is not set, and made to function as an input terminal according to setting when it should be made to function as a terminal for input, and to provide an input/output circuit for achieving that. SOLUTION: An input/output circuit 30 installed between a terminal 10 used for input/output and an integrated circuit 40 is provided with input circuits 31, 35 and 37 connected from the terminal 10 used for input/output through first capacitors C1, C3 and C5 to input terminals 41, 45 and 48 of an integrated circuit 40; and output circuits 33, 36 and 38 installed in parallel with the input circuits 31, 35 and 37, and connected from the terminal 10 used for input/output through resistances R1, R2 and R3 for impedance matching and the serial connection of the second capacitors C2, C4 and C6 to output terminals 43, 47 and 49 of the integrated circuit 40. When the terminal 10 used for input/output is used as a terminal for input, the output terminals 43, 47 and 49 are put in a mute state. COPYRIGHT: (C)2008,JPO&INPIT
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