| 摘要 |
PROBLEM TO BE SOLVED: To feed a stable power-supply voltage without increasing the number of external terminals by arranging at least either one of the first or second block for input/output of power supply between the first or second signal input/ output. SOLUTION: Firstly, a power-supply noise 18 caused by the operation of an internal circuit is conducted to a signal input/output block for the internal circuit. Then, a power-supply noise 19 caused by the operation of the signal input/output block for the internal circuit and the power-supply noise 18 are almost absorbed in a power-supply feeding source, before they are conducted to a signal input/output block for a high-S/N circuit which feeds a power-supply to the high-S/N circuit. This absorption is performed via a power-supply feeding input/output block and via a power-supply-noise absorbing routes 20, 21 whose impedances are very lower than the one of the conduction route to the high-S/N circuit. The foregoing is the example of the case wherein only one-side of signal input/output block for the high-S/N circuit is adjacent to the signal input/output block for the internal circuit.
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