Speaking of USB-C, this little doohickey, the “PocketPD”, has proven more useful than I expected when I ordered it on a whim from Crowd Supply. It basically lets you turn a USB-C power brick into a (noisy but usable) variable CV or CC bench supply. But it has earned its keep just as a test tool for showing what PD and PPS voltages and currents a supply can deliver (which are often quite different from what’s on the label). https://www.crowdsupply.com/centylab/pocketpd
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As a bench supply goes, it’s OK in a pinch (it’s small enough to travel with), but is limited by the fact that USB-C switching chargers have a TON of RF modulation noise on their output. You can mitigate this somewhat with a ferrite choke on the power leads, but it’s never going to be clean enough for many radio applications.
Also, surprisingly few USB-C supplies can negotiate PPS across the full 3.3-21V range.
@mattblaze Aye, that sounds most like an excellent piece of USB PD test equipment + a fairly lousy value for a bench top power supply.
(My bench brick cost $60 and is clean enough for radio. But I wouldn’t want to fit it in a suitcase)
@cmdrmoto It’s fine if you need to substitute a missing oddball 17V wall wart in your hotel room, but I’ve gotten a ton more use out of it just looking at the initial menu to see what a supply can do.
(PPS is a relatively new addition to the USB-C ”standard” that allows a device to negotiate an arbitrary voltage and current limit within a range).
@mattblaze
OK, cool. PPS explains why my new USB-C PD power supplies also have a voltage range.
