Post by thread:[PIC]using pic's 12 i/o and r2r net, as DAC

part 1 169 bytes content-type:text/plain; (decoded quoted-printable) I am thinking about: using pic's 12 i/o and r2r net, as DAC, with op as buffer. is this way acceptible? any example? part 2 35 bytes content-type:text/plain; charset="us-ascii" (decoded 7bit)

On 5 Jan 2006 at 22:43, microsoftwarecontrol wrote: > I am thinking about: > using pic's 12 i/o and r2r net, as DAC, with op as > buffer. > > is this way acceptible? any example? Do not expect 12 bit accuracy. A real 8 bit DAC will probably be more accurate. Cheerful regards, Bob

> > is this way acceptible? any example? http://www.avr-asm-tutorial.net/avr_en/AVR_DAC.html The problem is the resistor tolerance and matching. Save yourself a lot of work and buy a proper 12-bit DAC

At 10:43 PM 1/5/2006 -0500, you wrote: >I am thinking about: >using pic's 12 i/o and r2r net, as DAC, with op as >buffer. > >is this way acceptible? any example? Yes, you can do this. With 0.1% resistors you can approach 11-12-bit accuracy *typically*, but you'll need a decent buffer on the output. Don't expect it to be monotonic. >Best regards, Spehro Pefhany --"it's the network..." "The Journey is the reward" spam_OUTspeffTakeThisOuTinterlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com ->> Inexpensive test equipment & parts http://search.ebay.com/_W0QQsassZspeff

On 1/6/06, Spehro Pefhany <.....speffKILLspam@spam@interlog.com> wrote: > At 10:43 PM 1/5/2006 -0500, you wrote: > >I am thinking about: > >using pic's 12 i/o and r2r net, as DAC, with op as > >buffer. Order a maxim <shiver> sample.. Good analog chips, sometimes sourcing problems.. but for a one-off, just get a sample.. or get a microchip DAC sample. andrew

Maybe he is more interested in the learning aspect? Building ladder networks can be educational, after all. I've got a homebrew VGA adapter built with an FPGA and 3 resistors for each colour channel....works remarkably well. -marc On 1/8/06, andrew kelley <leetslackerKILLspamgmail.com> wrote: {Quote hidden}> > On 1/6/06, Spehro Pefhany <.....speffKILLspam.....interlog.com> wrote: > > At 10:43 PM 1/5/2006 -0500, you wrote: > > >I am thinking about: > > >using pic's 12 i/o and r2r net, as DAC, with op as > > >buffer. > > Order a maxim <shiver> sample.. Good analog chips, sometimes sourcing > problems.. but for a one-off, just get a sample.. or get a microchip > DAC sample. > > andrew > > -