I've thought about this all night and I keep coming to this question: What do you have that can measure current accurately enough to test something like this? -Denny ----- Original Message ----- From: "Eric Christensen" To: Sent: Saturday, October 18, 2003 6:10 AM Subject: Re: [EE]: high resolution DAC > Sorry... I wasn't very clear on that. > > I need to be able to set the current within 1% of 1 uA. > > So 3 amps must really be 2.99999999 to 3.00000001 amps. The hardware to > control the current this accuratly is being developed by someone else. > The initial plan, however, calls for the current be controlled by a > proportional voltage. When I starting punching in the numbers for this, > I was pretty much stumped. A 24 bit DAC seems to be about the only > thing precise enough. Otherwise we will need to implement the multiple > range setup. > > Eric > > > > On Sat, 18 Oct 2003 11:54:17 +0200 > "Jan-Erik Soderholm XA (TN/PAC)" > wrote: > > > Eric Christensen wrote: > > > > > I'm working on a current limited power supply that must control > > > current from 0 to 4 amps with 1 uA resolution with less than 1% > > > error. > > > > > > Hi. > > > > 1% of what ? Full scale ? Or 1% of 1uA ? > > > > 1% of 4A (full scale) is actualy 40000 uA !! > > > > Lets say you are outputing 4A, what is then the > > allowed "error" (expressed in Ampere !) ? > > > > Jan-Erik. > > > > -- > > http://www.piclist.com hint: To leave the PICList > > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > > > Eric Christensen > Iowa State University > Computer Engineering and Computer Science > Home: (515) 572-7708 > Cell: (612) 202-9336 > echris@iastate.edu > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads