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Honored ContributorNCO phase drift
Hello, I have an NCO generating a 60 Hz sine output. input clk = 10 khz phase accumulator precision = 32 bits angular resolution = 32 bits magnitude precision = 10 bits phase incr...
Altera_ForumHonored Contributor
Honored Contributor --- Quote Start --- Unlikely. NCO implements simple modulo integer arithmetic. The given constant will result in an excact output frequency of 10e3*25769804/2**32 = 60, within the accuracy of the crystal generating the 10k input frequency. Ignorant question, how do you determine "phase drift over time"? Comparing with mains frequency? Then you'll likely see a "drift". P.S.: I presume that "drift" doesn't mean the phase jitter of one input clock period. --- Quote End --- Yes I am comparing it with mains frequency. No not the jitter of the one input clock period. The phase of the nco constantly drifts one way or the other. If I increase the frequency of the input clock the drift increases in speed.
