Chris, take a look at Fairchild's (formerly Micro Linear's) ML2036
Programmable Sinewave Generator. All you need is a crystal
(literally, no capacitors). It requires +/- 5V and has a 3-wire SPI-style
interface. You clock-in 16 Bits, LSB first, and set a Latch Enable line to
set the frequency from 1 to 50KHz (I tested it to 65,535KHz). By using a
8.388608MHz crystal (Digi-Key PN: SE3415 / Epson CA-301 family), you get a
direct one-to-one program data to frequency setting with a 1Hz resolution.
The chip provides Osc/2 and Osc/8 outputs which may be of use if you want
to clock a PIC at 4.194304MHz.

   There is a voltage reference input. Tying this to +5V gives a maximum
output swing of +/- 2.5Vp-p. You can reduce this via an external reference.
Harmonic distortion is -45db max. The device comes in a 14-pin DIP or 16-pin
SOIC package. For more info:

      http://www.fairchildsemi.com/pf/ML/ML2036.html

   - Tom

At 21:16 06-01-02 -0500, Chris Eddy wrote:
>I want to add a synthesizer peripheral to a PIC processor to form a high
>accuracy frequency generator that can be adjusted down to the hertz and
>is stable as the crystal that drives it. I need 10K to 50KHz. All of the
>synthesizers that I can find all start with '2.2GHz synthesizer ideal
>for cell phones..'. You get the picture.
>
>Has anyone used a peripheral that they really like a lot?
>
>Thanks
>Chris~


------------------------------------------------------------------------
Tom Handley
New Age Communications
Since '75 before "New Age" and no one around here is waiting for UFOs ;-)

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