That would be very nifty. They have a DDS (or at least a patent on one) that uses CORDIC to generate the samples, rather than a table of sin/cos, so that might be a good start. I suppose it's a matter of trading silicon for the lookup table for silicon for the complex multiplier. And, I would think they'd want to still have the table, so the user can control with a phase increment, rather than cos(increment) and sin(increment).
On 8/16/09 11:33 AM, "Rick Karlquist" <[email protected]> wrote: > Lux, Jim (337C) wrote: >> >> The usual DDS chips (e.g. From Analog Devices) have a built in table of >> fixed length. If you want to use something other than the power of 2 it >> comes with, you'll need to implement the NCO in an FPGA, with an external >> DAC. > > Analog Devices is working on a variable modulus DDS, that should > eliminate the need to roll your own with an FPGA. > > Rick Karlquist N6RK > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
