SEMICONDUCTOR INTEGRATING CIRCUIT WITH BUILT-IN MEMORY

摘要

PURPOSE:To decrease power consumption, to improve an action speed of ROM and to decrease a chip size of LSI by executing the dynamic action and the static action for the X decoder in accordance with respective modes of a micro computer and an EPROM. CONSTITUTION:In an X decoder 22, only when a precharging signal phip goes to be H by a micro computer in which a signal EPM is L, an MOSFETQp goes to be on, a main decoder DEC is precharged, and address signals A1-A7 are decoded in accordance with a charging and a precharging of a node n1. On the other hand, a signal EPM is an EPOM mode of H, Qp is always on, a node n1 is held to H, Qd1-Qd4 are on, and then, the output of a main decoder DEC goes to be L. Thus, in the decoder 22, a main decoder DEC executes the dynamic action at the micro computer mode and executes the static action at the EPROM mode.