My mistake (as I said, I'm new to schematics and am prone to make some mistakes along the way :-) I am in fact using a 50uH inductor... otherwise as you said, it absolutely wouldn't work, heh. Quoting Tal : > Dave is right > in my PSU I use 47uH (farnell) inductor. > Tal > > -----Original Message----- > From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU]On > Behalf Of Dave Dilatush > Sent: Wednesday, March 05, 2003 5:40 PM > To: PICLIST@MITVMA.MIT.EDU > Subject: Re: [EE]: Project testing > > > Jai wrote... > > [details snipped] > > >...I figured connected the > >resistor connected right from +Vcc to GND would draw (V/R: 5V/10ohms) 0.5A. > > That's correct: a 10 ohm resistor connected across 5 volts will > draw 1/2 ampere. > > [tragic tale of fried regulator chip snipped] > > >...So I can't figure out what's going on (and I > >only have one more MAX787 left, heh). Is this not a good way to draw > current > >from the circuit? > > It's a perfectly valid way to test your supply. > > >Also on a side note, my circuit is current on a solderless breadboard. Are > >these things suitable for handling currents up to 1.5A? Could this be the > >problem? > > Solderless breadboards are [allegedly] good for some things, but > they sure aren't any good for building high-current switching > regulator circuits: the connections have way too much contact > resistance, meaning there will be large, unintended voltage drops > everywhere along the current path. I would be extremely > surprised if the circuit worked at all, and very unsurprising if > it malfunctioned destructively. This could indeed be the > problem. > > The data sheet for the MAX787 shows a typical application > circuit, and this circuit uses a 50 uH (50 microhenry) inductor. > Yet your schematic shows a 50 mH (50 MILLIhenry) inductor. What > gives? You should be strictly following the inductor selection > guidelines given by the chip manufacturer. If you really are > using a 50 mH inductor, this absolutely, positively will not > work. > > Dave D. > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. > ---------------------------------------- This mail sent through www.mywaterloo.ca -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.