I bought a DDS (AD9850) module for Arduino. I plan to build a simple (and cheap) USB function generator. The module outputs square and sine wave forms. And works up to 40MHz for sine, and 1MHz for square. At 20MHz sine waveform goes down to 165mVpp (at lower frequencies, and up to 1MHz it's 1Vpp). Square waveform is Vcc..GND and to 20MHz it's like a sine of 1.3Vpp
Anyway, I don't plan to build a professional function generator. In Buenos Aires, buying a professional one would take 300 USD at least. But I want to make the best I can with this little toy.
Let's get to the point
I have a couple of ideas for adding some functionality. But not sure how to implement them, or if they are going to work (at least in theory).
Should I protect the output? How?
Anyway, I don't plan to build a professional function generator. In Buenos Aires, buying a professional one would take 300 USD at least. But I want to make the best I can with this little toy.
Let's get to the point
I have a couple of ideas for adding some functionality. But not sure how to implement them, or if they are going to work (at least in theory).
- Increasing/decreasing output frequency as fast as I can (according to datasheet changing frequency would take 500ns) but it doesn't specifies a maximum frequency changing rate.
- Amplifying the output signal.
- Transforming the output signal into another waveform.
Should I protect the output? How?