PURPOSE:To prevent crosstalk from generating in a digital signal and an analog signal by a method wherein the low-sensitivity analog terminals of an analog functional cell and the digital terminals of a digital functional cell are respectively led out on both of the upper and lower sides of both functional cells and an analog land wiring, a reference voltage wiring and an analog land wiring for shielding use are built in a standard cell. CONSTITUTION:In an analog functional cell, an analog land wiring region AGND wiring, a reference voltage wiring region VREF wiring and analog land wiring regions for shielding use AGS1 and AGS2 wirings are contained. An isolation region given the potential of the AGS2 wiring is formed in the lower layer of the AGS2 wiring. Moreover, a high-sensitivity analog terminal is led out on the upper side of the cell, low-sensitivity analog terminals are led out on both of the upper and lower sides of the cell by providing an equivalent circuit and a digital terminal is led out on the lower side of the cell. In a digital functional cell, analog land wiring regions for shielding use AGS1 and AGS2 wirings are built in. An isolation region given the potential of the AGS1 wiring is formed in the lower layer of the AGS1 wiring. Moreover, digital input/output terminals are led out on both of the upper and lower sides of the cell by providing an equivalent terminal. As a standard cell, an isolation cell is prepared.
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