The list server on this list is incredibly sensitive to such minutia. If I use the wrong return address, it ignores what I send, and does not even say anything about it. Methinks it is far too picky.
----- Original Message ----- To: "Multiple recipients of list CHIPDIR-L" <[email protected]> Sent: Sunday, September 18, 2005 8:24 PM > (I tried sending this yesterday but, because of a slight difference in my > return email address, it seems to have been quietly dropped by the server) > > > The advice regarding the ceramic bypass capacitors is good as far as it > goes, but, if your problem is a power supply which compensates slowly > for load changes, you might try some bulk capacitance across the 3.3V > input to the board as well (a large electrolytic). This should partly > take up the initial changes in current so that the power supply has the > time to respond and prevent serious falls and rises in the output > voltage. > If it is slow response in the supply, you should see the voltage spikes > at its output not just near the FPGA. > If adding bulk capacitance does not work, you may have to consider using a > better power supply to provide the 3.3V > > > > On Sat, 2005-09-17 at 15:39 -0800, Uwe Zimmermann wrote: >> ...plenty of fast capacitors (ceramic, not electrolytic) close to the >> supply pins of the chips, short and wide power lines... >> >> Uwe. >> >> >> > hi, >> > here is a weered problem i stuck with developing a board of mine. >> > it's a very heavy loaded board with many FPGA's on that "eat" a lot of >> > power (100W) >> > the problem is that those FPGA's do a heavy work once every 2msec wich >> > creates power drop of about 0.2 volt. >> > it results with the voltage looking like this: >> > /\ ___/\ ___ >> > \/ \/ >> >> > where the mean voltage is 3.3V >> >> > anyone know how to deal with thease voltage dropout (thy cause >> > malfunctioning of the curcit) >> >> > regars, Michael >> >> > -- > Bob Mitchell > PO Box 68 Phone (+61 2) 9449 4736 > (21 Hudson Close) Fax (+61 2) 9449 1976 > Turramurra, 2074 Mobile 0411554117 > NSW, Australia Email [EMAIL PROTECTED] > > > -- > Author: Robert Mitchell > INET: [EMAIL PROTECTED] > > Fat City Hosting, San Diego, California -- http://www.fatcity.com > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB CHIPDIR-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Author: Syd H. Levine INET: [EMAIL PROTECTED] Fat City Hosting, San Diego, California -- http://www.fatcity.com --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
