| 摘要 |
PURPOSE:To always detect a substrate potential correctly and to control a feedback without delay by a method wherein a detecting part of a substrate potential detector is installed near a maximum leakage-current source of a potential change in a semiconductor substrate. CONSTITUTION:An FET Q1 used as a maximum leakage-current source is formed in an FET substrate 1. A detecting part (detecting terminal) of an SD 2 is installed near the FET Q1. The SD 2 detects a substrate potential VSD near the FET Q1, outputs a feedback signal FB to a substrate-potential generation circuit (BBG) 3 and adjusts a potential-output capacity of the BBG 3. The BBG 3 supplies a substrate potential VBB to the FET substrate 1 on the basis of the feedback signal PB. The FET Q1 generates a substrate leakage current by means of a switching operation and changes the substrate potential near the FET Q1; however, since the SD 2 has detected the potential near the FET Q1 in advance, it can quickly change a capacity of the BBG 3, and the substrate potential is stabilized. |
