| 摘要 |
<P>PROBLEM TO BE SOLVED: To quickly return from a self-refresh mode. <P>SOLUTION: For example, a controller 50 issues a self-refresh command SRE to a semiconductor device 10 and makes the semiconductor device enter a self-refresh mode. After entering the self-refresh mode, the semiconductor device 10 executes refreshing operations periodically by using an oscillator 150. In the self-refresh mode, time period required for one refreshing operation is shortened to a quarter of a time period required in an auto refresh, and the execution frequency of the refresh operation is raised by four-times. Thus, after issuing a self-refresh exit command SRE, a time period where input of a row system command is prohibited is shortened. <P>COPYRIGHT: (C)2013,JPO&INPIT |
