Question
Do you have a 14-bit DDS chip with Triangle Output, faster than 75MHz.
Answer
Unfortunately our series of DDS Waveform Generator parts are limited to 10-bits
of resolution.
Only certain DDS parts can switch between a sine-wave, triangle-wave, or a
square wave output. These parts are the AD9833/AD9834 and AD5930/AD5932. The
highest operating frequency of these parts is the A9834 at 75MHz.
However, it seems some of our higher speed DDS parts (>75MSps) like the
AD9910/AD9911 can be modified to output triangle outputs, please see the
following thread on Engineer Zone (post by DSB):
http://ez.analog.com/message/23245#23245
It is recommended to get an evaluation board to evaluate this capability.
Note, in this mode the max effective DAC sample rate is the SYNC_CLK rate or
1/4th the system clock rate.
The reason, the sweep circuitry is clocked at the SYNC_CLK rate not the system
clock.
So, the input sample rate to the DAC input (to form a triangle waveform via
Sweeper) equals the SYNC_CLK * x where x ranges from ( 1 to 2^16).
X represents the Digital ramp rate register 0x0D.
This this will produce a sampled triangle waveform, if it is required to filter
this sampled waveform it could distort the waveform at the filtered output.