Are there programmable tone generator ICs out there? It would have a digital interface to a microcontroller (e.g. I2C). Through this interface the controller could set a tone and volume. The output would go to a fixed-gain audio amp and then to a speaker, or may be the tone generator IC would have an amplifier on board.
The closes thing I was able to find is this: http://www.keterex.com/pubs/kx1400ds.pdf . The tone generator is a part of an audio playback chip. May be there are other audio codec type chips that have tone generators and volume control…
Any suggestion (aside from obvious) or insight is appreciated!
Worked with Analog Devices' DDS chips in the past. I haven't seen a DDS chip with programmable amplitude (volume). Of course, one of the solutions would be to connect the fixed amplitude output to a programmable gain audio amp.
It's not clear from your post, if you intend to generate pure sine waves or musical tones. In the latter case, a sound synthesizer chip, that understands MIDI commands, would be a more versatile and better sounding solution, I think.