| 摘要 |
PROBLEM TO BE SOLVED: To prevent the deterioration of the SN ratio of a delta sigma type analog-to-digital converting circuit or digital-to-analog converting circuit formed on a semiconductor device due to crosstalk noise detouring through a substrate. SOLUTION: On the semiconductor device, a plurality of regions A and B electrically separated from each other by pn junction separation or insulator separation is formed and a switched capacitor and a digital filter causing crosstalk are disposed dividedly in the regions A and B. Consequently, the high-performance analog-to-digital converting circuit or digital-to-analog converting circuit which can easily prevent the deterioration of the performance of the circuit in the SN ratio caused by the crosstalk noise detouring through the substrate 5 without requiring the setting of complicated operating timing can be provided. At the same time, a plurality of asynchronous analog-to-digital converting circuits or digital-to-analog circuits can be provided easily in one semiconductor device. COPYRIGHT: (C)2005,JPO&NCIPI
|
