-------- Bob wrote: > You could also say that with a longer accumulator, you get a closer > approximation to a desired waveform.
The width of the accumulator does improve the waveform, but only if you need a frequency between the ones possible with the more narrow accumulator. It goes without saying that the extra bits only have an effect if they are non-zero. Mike write: > I do not believe that is true. Only a longer D/A would result in a closer > approximation to the desired waveform. Adding non-linear bits to the DAC increases noise significantly, because it introduces a periodic effect. This stuff is all easy to simulate with a computer. Try simulating a 12 bit Dac and a 14 bit DAC where the LSB is only half the magnitude it should be. If I were trying to build a high-res DDS, I would calibrate the sine-table to the specific DACs imperfections. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [email protected] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
