| 摘要 |
<p>An integrated circuit (1) receives an external clock signal (CK-ext) and in addition has a random generator (2) which produces a random clock signal (CK-al). The external and random clock signals are applied to a switching circuit (3). The switching circuit (3) is controlled by signals (K) from a group of circuits (5) including memories, data and processors and operates to select either the external or random clock signal for entry to the internal clock signal generator (4). The clock signal selection is such that the external signal is only used for external synchronisation.</p> |
