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RussMartin
- 21st November 2007, 06:49
I'm looking for suggestions on a DAC.

Requirements (for the moment) are 5 volt single-ended supply, 8-bit parallel, and DIP package.

Anyone have any old (or new) favorites they'd care to recommend?

Jumper
- 21st November 2007, 08:30
Hi,

A R2R network and a generic op-amp would do the trick or the HPWM+filter plus an extra op-amp if you need more current is also one way. Then you only need one pin from the PIC.

I haven't found a need for an external DAC since these 2 ways have been enough this far.

/me

Ioannis
- 24th November 2007, 17:55
For the recommended methods by Jumper, care should be givet to the selection of op-amps, since the requirement is 5V power supply.

If you can tolerate serial communication, then ADC0831 is a nice part.

Otherwise, ZN426 could also be used on 5V rail.

Ioannis

Darrel Taylor
- 24th November 2007, 21:01
The new D/A from Microchip looks interesting (MCP4725).
Sorry, it's not the parallel device you're looking for.

12-bit, op-amp Buffered output, I2C, with EEPROM, SOT23-6.
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1335&dDocName=en532229

http://news.thomasnet.com/fullstory/536152

So new I'm not sure if you can even get them yet.

.

RussMartin
- 25th November 2007, 06:21
Well, except for the 5V requirement, this looks like it might do the job:

http://focus.ti.com/lit/ds/symlink/tlc7226.pdf

Since I need two DACs, this may solve the problem in one package. And I do have an unregulated 16.5 VDC available.