I bought a real cheap toy keyboard that has one IC in it, and it's almost a step-and-a-half flat.
I thought maybe the tuning of the thing might be determined by an associated crystal (fat chance!) or maybe an associated RC circuit. I can't find info on this IC. Anyone know anything about it?
**broken link removed**
It's not too complicated, so I can probably derive the schematic.
There is a stereo amplifier IC from Toshiba that carries the 2025 base number -- and UTC makes a version of that IC that can be used as a "bridge" amplifier as well. The IC is the TEA2025 (UTCTEA2025), and I have uploaded **broken link removed**for it. Maybe this will help??
Thanks for trying. This can't just be a linear amplifier, because the darn thing has a bunch of functions. It's got a variety of instrument sounds, drums, demo tunes, etc. This has got to be an on-board computer/synthesizer, I think, unless there's another real-well hidden IC or two that I missed...
Now that I give it some more thought, though, and having seen this datasheet...