A delay locked loop (DLL) that applies an amount of delay to an external clock signal to generate multiple delayed signals. One of the delayed signals is selected as an internal clock signal. The multiple delayed signals have different delays in relation to the external clock signal. If a change in operating...http://www.google.de/patents/US6937530?utm_source=gb-gplus-sharePatent US6937530 - Delay locked loop “ACTIVE Command” reactor
