微电子专业外语2.ppt

Basic MOS Device Physics Fig. 2.4 indicates an interesting difference between NMOS and PMOS transistors: while all NFETs share the same substrate, each PFET can have an independent n-well. 注意： while Design of Analog COMS Integrated Circuit Basic MOS Device Physics This flexibility of PFETs is exploited in some analog circuits. The circuit symbols used to represent NMOS and PMOS transistors are shown in Fig.2.5. 注意： flexibility，exploited， use Design of Analog COMS Integrated Circuit flexibility， exploited flexibility [英] [?fleks??b?l?t?] [美] [ ?fl?ks??b?l?t?] n. 柔韧性，机动性，灵活性 exploit vt. 开采； 开拓； 利用（……为自己谋利）； 剥削 近义词 advantage得益，获利 Design of Analog COMS Integrated Circuit use used to是“过去曾经...”的意思 ，后接动词 比如：He used to be a teacher。他曾经是一名教师 I used to go swimming once a week。我曾经每周都去游泳 be used to是“习惯...”的意思 ，后接名词 He is used to getting up early.他习惯了早起 Mary is used to her husband‘s bad temper. Mary习惯了她丈夫的坏脾气 Design of Analog COMS Integrated Circuit use get used to强调的是由“不习惯”到“习惯”的这个过程，而“be used to”所强调的只是“习惯了”这个状态 Design of Analog COMS Integrated Circuit Basic MOS Device Physics The symbols in Fig. 2.5(b) contain all four terminals, with the substrate denoted by B (bulk) rather than S to avoid confusion with the source. 注意： avoid +n/-ing Design of Analog COMS Integrated Circuit Basic MOS Device Physics The source of the PMOS device is positioned on top as a visual aid because it has a higher potential than its gate. 注意： as a visual aid作为视觉辅助 Design of Analog COMS Integrated Circuit Basic MOS Device Physics Since in most circuits the bulk terminals of NMOS and PMOS devices are tied to ground and Vdd, respectively, we usually omit these connections in drawing Fig. 2.5(a). 注意： omit; in drawing Figxx Design of Analog COMS Integrated Circuit omit omit 是省略neglect是不经意的忽视 而ignore是故意不理 其他近义词skip, miss Design of Analog COMS Integrated Circuit Basic MOS Device Physics In digital circuits, it is customary to use the “switch symbols depicted in Fig. 2.5(c) for the two