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I know the Fmax for MC100LVEP210 is 3GHz, but is there an Fmin requirement?
ECL can operate from sub-hertz (<1.0 Hz) frequency to fmax if all parameters are within limits and input edges are sufficiently fast. The fastest edges accepted at the inputs are “generally” the datasheet output tr/tf min spec; and the slowest acceptable edges are “generally” about 10 us where the actual signal usability becomes the issue. Exceptions to this general rule will usually be indicated in the datasheet. The slowest edge limitation is due to environmental noise during the signal threshold crossing causing multiple “false clock” pulses. Edges slower than 10 us may work if the environmental noise is low enough or filtered sufficiently. Slower edges risk transitioning through the threshold transfer zone, crosspoint +/- about 10 mV, slow enough will force small signal “analog / op-amp” behavior (dV/dT) on the internal logic and outputs and may risk ambient, environmental input noise “gained” up and appearing on the output (as noise). Usually the application environmental noise on the input limits will effectively limit the useful edge rates, not the device internal logic structures.
Answered by: ON Semiconductor
2014-10-20 14:03:34.547