I am looking for a design of a PCB and one prototype of a circuit which has two outputs, one with a sinewave and one with a cosine, i.e. phase shifted 90 degrees relative to the other output. The frequency should be programmable from 100 Hz to 1000 Hz, and the amplitude is not important, it can be a few volts.
I am planning to implement this by controlling two DDS chips, e.g. AD 9835's or something like that, with the Arduino UNO. So what I am looking for is:
1. a circuit board with two DDS chips which have their clocks locked to one another so their timing is accurate relative to each other and which put out a sine and a cosine. This board should have connectors for lines both for the outputs and for the digital controls which come directly from the Arduino UNO. For deliverables I want a layout in something like express PCB which can easily be translated into a purchased board cheaply and one fully stuffed and tested board, as well as a documented schematic.
2. Commented and transparent Arduino code to control the frequency of both of the chips.
The ultimate goal here is to have a programmable frequency sine/cosine generator. I am not an expert on modern digital electronics. I am looking for a solution to this problem which is reasonably transparent and easy to implement, and if you suggest a better way to do this, feel free to bid based on that. Ultimately this is going to be an "open source" design, and the more transparent the design is to other people who might want to implement it the better.