On Wed, 23 Jan 2008 16:39:02 +0200 "Dumitru Stama" wrote: > This is almost the value I should get by sending "250" to the DAC but > instead I get 2.35, > almost half of what it should be. Am i right here ? I'm guessing you are not connecting to the correct node of the R/2R network. 10k/20k should work well with the PIC outputs. Note that there are two different applications for R/2R: One uses an opamp at the output and works with currents (http://www.allaboutcircuits.com/vol_4/chpt_13/3.html) the other one is designed for volrages (http://www.avr-asm-tutorial.net/avr_en/AVR_DAC.html - note that the opamp here is only as a voltage follower, not current to voltage converter). John -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist