Mikhail, what you need to do is maintain a low enough impedance on the load side. The resistor / etch drawbridge or other method will introduce a substantial inductance that you will need to compensate for with a suitably low inductance capacitance on the other side, that also does not resonate with the inductance in your signal frequency range. What I would recommend you do if you can is place your current sense back at the VRM, and then measure with your chip of interest at quiescent versus active. The quiescent on most FPGAs and DSPs can be made pretty small. This way you don't need extra parts in your bypass network, and you won't starve your parts. Steve. Mikhail Matusov wrote: > Hi all, > > Is that a really bad idea to insert a small current sensing resistor, e.g. 3 > mOhm, followed by a bulk capacitor in each power rail of a let's say a DSP > or a FPGA chip to be able to measure its power consumption? > > > Thanks, > ======================= > Mikhail Matusov > Senior Hardware Design Engineer > Square Peg Communications > Tel.: +1 (613) 271-0044 ext.231 > Fax: +1 (613) 271-3007 > http://www.squarepeg.ca > > > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list > > For help: > si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > > > List technical documents are available at: > http://www.si-list.net > > List archives are viewable at: > //www.freelists.org/archives/si-list > or at our remote archives: > http://groups.yahoo.com/group/si-list/messages > Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > > > > -- Steve Weir Teraspeed Consulting Group LLC 121 North River Drive Narragansett, RI 02882 California office (866) 675-4630 Business (707) 780-1951 Fax Main office (401) 284-1827 Business (401) 284-1840 Fax Oregon office (503) 430-1065 Business (503) 430-1285 Fax http://www.teraspeed.com This e-mail contains proprietary and confidential intellectual property of Teraspeed Consulting Group LLC ------------------------------------------------------------------------------------------------------ Teraspeed(R) is the registered service mark of Teraspeed Consulting Group LLC ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu