| 摘要 |
PURPOSE:To decrease the effect of noises generated in a power source wiring on internal circuits, by independently providing a power source wiring, which supplies a potential corresponding to a substrate potential, and a power source wiring, which supplies the substrate potential to the substrate, in a plurality of internal circuits formed on the same semiconductor substrate. CONSTITUTION:Source electrodes 104 and 106 of N-type MOSFETs 103 and 105 are connected to a first power source pad 101 through a first power source wiring 102, which supplies a potential corresponding to a substrate potential to internal circuits. A P-type substrate 100 is connected to a second power source pad 107 through a substrate electrode 109 and a second power source wiring 108, and the substrate potential is supplied to the substrate. Even if noises are generated in the first power source wiring 102 due to the operations of the internal circuits, noises are not generated in the second power source wiring 108. Therefore, the substrate potential is not fluctuated and it is kept at constant value. Erroneous operations of other circuits, which are connected to the internal circuits, due to the noises generated in the power source wiring of the circuit can be prevented. |
