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PCell stands for parameterized cell, a concept used widely in the automated design of analog integrated circuits. A PCell represents a part or a component of the circuit whose structure is dependent on one or more parameters. Hence, it is a cell which is automatically generated by electronic design automation (EDA) software based on the values of these parameters. For example, one can create a transistor PCell and then use different instances of the same with different user defined lengths and widths.〔(【引用サイトリンク】url=ftp://ftp.sitsemi.ru/pub/Cadence/pcellref.pdf )〕 Vendors of EDA software sometimes use different names for the concept of parameterized cells, e.g. ''T-Cell'' and ''Magic Cell''. == Application == In electronic circuit designs, cells are basic units of functionality. A given cell may be placed or instantiated many times. A PCell is more flexible than a non-parameterized cell because different instances may have different parameter values and, therefore, different structures. For example, rather than having many different cell definitions to represent the variously sized transistors in a given design, a single PCell may take a transistor's dimensions (width and length) as parameters. Different instances of a single PCell can then represent transistors of different sizes, but otherwise similar characteristics. The structures within an integrated circuit and the rules (design rules) governing their physical dimensions are often complex, thereby making the structures tedious to draw by hand. By using PCells a circuit designer can easily generate a large number of various structures that only differ in a few parameters, thus increasing design productivity and consistency. Most often, PCell implies a ''physical PCell'', i.e., a physical representation of an electronic component describing its physical structure inside an integrated circuit (IC). Although most PCells are physical PCells, device symbols in circuit schematics may also be implemented as PCells. Underlying characteristics of all PCells are a dependence on (input) parameters and the ability to generate design data based on these parameters. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「PCell」の詳細全文を読む スポンサード リンク
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