Hi all
QRP Labs kits are heavily dependent on the Si5351A from SiLabs. Sadly?this chip is a victim of the ongoing global semiconductor shortage, and perhaps also the acquisition by SkyLabs, of parts of Si5351A business including the clock generator ICs.?
At the same time there is a new substitute chip MS5351M which has good availability, and has been recommended by several correspondents; I am also aware of some kit vendors already using the MS5351M in their products. Clearly it "works". However, the MS5351M documentation is very sparse and I have not seen any actual performance measurements or comparisons documented. To gain enough confidence to be able to start using this chip I undertook as many detailed measurements as I could, including phase noise measurements and use in QCX-mini CW transceivers, and documented them here:
The conclusion is that the MS5351M is a 100% direct substitution for Si5351A and has slightly improved performance in some areas. In my opinion, MS5351M can be used in place of Si5351A in any hobby project or commercial product.?
Due to my substantial former purchases as the global semiconductor shortage was getting underway, I still have a stock of around 1,000 Si5351A ICs but it is inevitable that going forward, in order to continue production of QRP Labs kits, we will start to use the MS5351M in some manufacturing batches.?
Much as I dislike cross-posting normally, I am cross-posting this one to other QRP discussion groups in the hope that the measurements may be of interest to some. Many of us use the Si5351A in our hobby projects and some of us in our commercial products too. This is previously unpublished information that I have not seen anywhere else.
73 Hans G0UPL
