METHOD AND APPARATUS FOR INITIALIZING A DELAY LOCKED LOOP

摘要

A delay locked loop includes initialization circuitry that ensures that a DLL
is initialized to an operating point that is not to close to either end of a
delay vs. control voltage characteristic. The initialization circuitry forces
the DLL to initially search for a lock point starting from an initial delay,
the delay is varied in one direction, forcing the DLL to skip the first lock
point. The initialization circuitry only allows the DLL to vary the delay of
the voltage controlled delay loop in the one direction from the initial delay
until the operating point is reached.