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AR# 6362

UniSim, SimPrim, Simulation - When I simulate a DCM or CLKDLL, the LOCKED signal does not activate unless simulation is run in ps time resolution


When I simulate a DCM or CLKDLL, the locked signal does not go High, and the DCM or CLKDLL do not function properly unless the simulator resolution is set to picoseconds.


Due to the wide range of frequencies that the DCM and the CLKDLL must handle, the UniSim and SimPrim simulation models must account for the fastest clock frequency. Since the models use picosecond (ps) resolution, the signal edges might be missed if you use any time scale larger than picoseconds during simulation.

To properly simulate the CLKDLL, change the time resolution so that is uses picosecond resolution.

AR# 6362
Date Created 08/21/2007
Last Updated 12/15/2012
Status Active
Type General Article