| 摘要 |
PURPOSE:To provide a master slice capable of increasing kinds of circuits selectively, in a circuit consisting of MISFET, by connecting two pieces of loading FETs in series and executing ion injection as required to turn them into depression type. CONSTITUTION:Loading FETs of a circuit are composed of a transistor LTr 1 made by connecting a gate and a drain with a Vcc power source and also of a transistor LTr 2 made by connecting a gate and a source with a drain and an output terminal of a driving FET (DTr). These two FETs are prepared to become E mode, and at the time of writing process of a ROM circuit to be connected to an input, for example, it is turned into D mode by execution of ion injection as required. This is to become possible to be utilized for various purposes simply by changing injection mask in such a manner that a pull-up resistance type by making injection on the both, a clamp-operating open drain type by injection only into the LTr 1, and if it is held in E mode, it becomes an open drain type circuit which has no clamping motion even at the time when a high voltage is impressed onto an output terminal. |
