The AD9850 is a highly integrated device that uses advanced
DDS technology coupled with an internal high speed, high
performance D/A converter and comparator to form a complete,
digitally programmable frequency synthesizer and
clock generator function. When referenced to an accurate
clock source, the AD9850 generates a spectrally pure, frequency/
phase programmable, analog output sine wave. This
sine wave can be used directly as a frequency source, or it can
be converted to a square wave for agile-clock generator applications.
The AD9850’s innovative high speed DDS core provides
a 32-bit frequency tuning word, which results in an output
tuning resolution of 0.0291 Hz for a 125 MHz reference clock
input. The AD9850’s circuit architecture allows the generation
of output frequencies of up to one-half the reference clock
frequency (or 62.5 MHz), and the output frequency can be digitally
changed (asynchronously) at a rate of up to 23 million new
frequencies per second. The device also provides five bits of
digitally controlled phase modulation, which enables phase
shifting of its output in increments of 180°, 90°, 45°, 22.5°,