I have two DDS AD9959.
I did experiment for synchronization of each DDS 4-channels using 'manual I/O update' button in supplied software.
The result is follow.
1. DDS1 2. DDS2
Figure 1. DDS1 synchronization Figure 2. DDS2 synchronization
In the figure 1, the channel 2 signal has amplitude offset and phase offset.
The phase offset is about 7 degree.
I experimented again, however the amplitude/phase offset is almost constant.
I could't find the range of amplitude/phase offset in the datasheet when the 4-channel output is synchronized.
I wonder if the amplitude/phase offset above figure is reasonable.
And, I want perfect synchronization of 4-channels that meas the amplitude and phase of all channels are same.
Could you tell me how to synchronize without phase offset?
I'm thinking about whether I should use a phase detector.
Thank you for reading.