Quote Originally Posted by Robin Hewitt View Post
Is it worth mentioning that a DAC is a simple resistor ladder
I've tried making DACs with R2R resistor ladders. They were OK, but not especially accurate due to the way the small errors accumulate. If you buy the resistors in a reasonable quantity then you can spend a bit of time with a meter matching them which can help a lot.

Probably easier just to buy the IC. Something like this:

http://uk.farnell.com/jsp/search/pro...sp?sku=8454647

(There's probably cheaper ones that are adequate - that's just one I've used before so I know it works easily!)