From 246tnt at gmail.com Sun Nov 8 20:12:06 2015 From: 246tnt at gmail.com (Sylvain Munaut) Date: Sun, 8 Nov 2015 21:12:06 +0100 Subject: Regulator Synchronization Message-ID: Hi, I know that on the UmTRX the switching controllers ( ST L5973 ) are all synchronized together. IIRC the earlier versions of the UmTRX didn't have this and I'm wondering if you really noticed a difference due to this change ? Cheers, Sylvain From andreysviyaz at gmail.com Wed Nov 25 11:33:26 2015 From: andreysviyaz at gmail.com (Andrey Sviyazov) Date: Wed, 25 Nov 2015 14:33:26 +0300 Subject: Regulator Synchronization In-Reply-To: References: Message-ID: Hi Sylvain. Sorry for so delayed reply, I've found that I've lost subscription for this mailing list. Well, actually DC/DC were synchronized (between each other) even in the very first UmTRX version. On the first versions I saw spurs from DC/DC ~500 kHz at the TxPLL noise plot (few in case of non-sync) and some other surprises. You can see issue #42 here: https://code.google.com/p/umtrx/issues/detail?id=42&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified Nowadays, we use DC/DC chip TPS54560, synchronized to 541 kHz signal (26/48) from FPGA. No surprises noticed anymore, but actually, we chose TPS54560 because of better efficiency and higher input voltage. Best regards, Andrey Sviyazov > ---------- Forwarded message ---------- > From: Sylvain Munaut <246tnt at gmail.com> > Date: Sun, Nov 8, 2015 at 11:12 PM > Subject: Regulator Synchronization > To: umtrx > > > Hi, > > > I know that on the UmTRX the switching controllers ( ST L5973 ) are > all synchronized together. > > IIRC the earlier versions of the UmTRX didn't have this and I'm > wondering if you really noticed a difference due to this change ? > > > Cheers, > > Sylvain > > -------------- next part -------------- An HTML attachment was scrubbed... URL: