Path: ...!Xl.tags.giganews.com!local-2.nntp.ord.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Mon, 24 Jun 2024 20:24:19 +0000 From: Joe Gwinn Newsgroups: sci.electronics.design Subject: Re: Interesting reading about spread-spectrum, also for on-board designs Date: Mon, 24 Jun 2024 16:24:19 -0400 Message-ID: References: <45mo6jhcq8kisjmbrom8i1r17ljr6g4qu8@4ax.com> <1o0j7jta3sqmtpp0ogu60jpf1lduql59q5@4ax.com> User-Agent: ForteAgent/8.00.32.1272 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 34 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-Da1bv9A8Gd+2efveFSHT3izCXA+fWucynKS6o2deIQgIx3kO0od76pl4xZoBxTlkyA0VNsGIgK9NaZB!LRO+xz2uXAR1QfSb4gZvJv3hHDrM/rC718f8QurcrsfrR25gHBEGG9+m6xTLmE2EAgin/5o= X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 2356 On Mon, 24 Jun 2024 07:53:56 -0700, john larkin wrote: >On Mon, 24 Jun 2024 10:32:50 -0400, Joe Gwinn >wrote: > >>On Fri, 14 Jun 2024 07:55:14 -0700, john larkin wrote: >> >>>On Fri, 14 Jun 2024 07:43:53 GMT, Jan Panteltje >>>wrote: >>> >>>>Interesting reading about spread-spectrum, also for on-board designs: >>>> https://www.electronicdesign.com/technologies/power/article/55041243/monolithic-power-systems-choosing-the-proper-parameters-in-frequency-spread-spectrum-fss-design >>> >>>That's cool, except for the usual dreadful fake pcb image. >>> >>>We have a bunch of switchers that use our own FPGAs as the >>>controllers, and I need to start up a project to make them >>>spread-spectrum. >>> >>>We don't want the ss modulation to show up in the DC outputs as ripple >>>or anything audible. >> >>Standard issue in radar systems. >> >>Take the FFT of the ss modulation and develop a pseudo-random sequence >>generator which shows no structure in the spectrum. >> >>Joe Gwinn > >And has minimal low-frequency content. Typically, yes. Joe Gwinn