| 摘要 |
PURPOSE:To simplify the constitution of a control circuit and to improve both the reliability and the maintenance properties, by securing such constitution where a refresh action is started by the 1st refresh start circuit when the 2nd clock is set in a continuous clock mode and said refresh action is switched by the 2nd refresh start circuit in a single clock mode respectively. CONSTITUTION:In a continuous clock mode the accesses produced from an access control circuit 4 are sent to a timing generating circuit 5 in the form of a start signal G0, an operator signal OPE, an address signal AD and a write signal WD respectively. A timing generating circuit 5 receives the signal G0 and starts a timing chain consisting of flip-flops FF10-16. The signal OPE is decoded by decoder DEC40, and the action modes for read R0, write WO and refresh RFO are set to FF18-20 respectively. In a read/write action mode a column address strobe RAS and a row address strobe CAS are turned on in the cycles T1 and T2 respectively and then turned off in the cycles T5 and T6.
|
