I am new to DDS. I search online to find a solution to generate arbitrary waveform and someone recommend me AD9910. I have some experience using an arbitrary waveform synthesis before. Since I have a limit budget, I cannot afford the eval board. I am going to build the circuit board myself. I have few questions
1) the manual said the expose pad must be grounded. Is the pad metal so I only have to wire the pad to the ground pin?
2) there is an internal clock up to 1GHz, do I still need an external clock to make it work?
3) If I build the circuit myself, what other elements I need to make it work?
4) I am not sure how waveform data pass to the chip. As my understanding, we could use parallel port. So will the waveform data store in somewhere in the chip before output or it will output the waveform in real time once it receive the data? It is quite confusing on this because in other waveform generator I used before, I upload everything to the RAM in advance. However, I read the manual and the RAM AD9910 has is just 1024x32bit. I am dealing with something about 300K at a time. If I send in parallel port, how long does it take to send the 300K data to the chip for output?