Re: Cinematronics > Atari Adapter???

You could use something like the DAC7541 which is under $11 even in
single lots. The op-amp following the DAC will determine the settling
time. Like Tom says, you can have the DAC only give a positive output
(in this case by using a negative reference for the DAC) to allow cheap
switches and subtract out the midpoint (using the same reference voltage
for best results) to get the desired output swing.

Really nothing much to it.

Tom McClintock wrote:

>Wait, here are some notes from Zonn.
>
>------------------
>Your biggest problem with doing a Cine->WG board is
>that you are forced to use 12 bit parallel DACs, which
>are expensive. The Cine design is pretty much going to
>force you to find ~1 to 2 us settling time parts. (To
>keep the frame rate up, we had to do the same.)
>
>Though you might be able to save some money by using
>single supply 12 bit DACs and shifting the voltage
>after the analog switch / RC stuff. This is the
>approach we took in the ZVG. This also allows the use
>of the much more available and less expensive 74HC4066
>switches which are only single polarity switches. The
>LF13331 were bi-polar, and also expensive (when they
>were available).
>
>You can't use serial DACs. They would require a
>parallel to serial conversion and there is no time
>allocated in the hardware to allow this. The DACs are
>latched and the Z-axis is turned on for the draw,
>there's no "clock data into DACs" time, which at
>minimum would take 16 clock cycles, if both DACs were
>simultaneously clocked.
>-------------------------------
>
>
>Beyond that, lemme know if you come up with something :)
>
>
>tm
>
>
>

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Received on Mon Oct 14 00:42:14 2002