| 摘要 |
<p>PURPOSE:To stabilize a signal level in an IC card, etc., by controlling the validity/invalidity of a control signal by means of a simple circuit in an electrically erasable P-ROM. CONSTITUTION:A control signal, the inverse of CTL is supplied to and gates 412-414 via the inverter 411 of a control circuit 41, and a read signal, the inverse of OE, a write signal, the inverse of WE, and a chip selecting signal, the inverse of CE are made valid/invalid corresponding to the level of the control signal, the inverse of CTL. With this constitution, in case of an IC card, etc., to which an additional circuit is hard to be provided, only by connecting an input terminal 47 for the signal, the inverse of CTL to a line through which a reset signal is supplied to the controller for such as microcomputer, the signal, the inverse of OE/the inverse of WE/the inverse CE can be made valid/invalid at the same timing as the action of the controller. As a result, an erroneous operation can be prevented from being occurred, and the signal level can be stabilized.</p> |
