Message-ID: <6670c7c1@news.ausics.net> From: not@telling.you.invalid (Computer Nerd Kev) Subject: Re: No More USB-A Ports Newsgroups: comp.misc References: <6664e474@news.ausics.net> <666f6a26@news.ausics.net> User-Agent: tin/2.0.1-20111224 ("Achenvoir") (UNIX) (Linux/2.4.31 (i586)) NNTP-Posting-Host: news.ausics.net Date: 18 Jun 2024 09:33:21 +1000 Organization: Ausics - https://newsgroups.ausics.net Lines: 65 X-Complaints: abuse@ausics.net Path: ...!weretis.net!feeder9.news.weretis.net!news.bbs.nz!news.ausics.net!not-for-mail Bytes: 3731 Dan Purgert wrote: > On 2024-06-16, Computer Nerd Kev wrote: >> Dan Purgert wrote: >>> Mine here are all 5/9/15/20V. I "think" they're missing only 1 or 2 >>> voltages, but that's enough for my laptops and cell phones. Not really >>> sure what'd ask for 9 or 15 volts ... >> >> 9V plugpacks are pretty common for stuff I use, it's typical for >> devices that reduce that to 5V internally. Similarly 5V devices >> generally use 3.3V internally. My laptop's power supply is 16V, so >> 15V might work. > > Not sure what a "9v plugpack" is -- maybe something leaning a little > more "professional grade", like what photographers tend to carry about? As Rich suggests others call them wall warts, though I thought plugpack was actually the more universal term for them. Power supplies with a mains connector built into the enclosure, including USB ones. Not only supplied with things that charge batteries or perform computer functions. >> Yes it's all rather complicated, but in theory a device to allow >> manual control of the output could be quite cheap because there >> are chips designed for doing that in relatively dumb USB-C-powered >> devices. However I found a project online from someone who'd tried >> making a bench power supply adapter from a wide-range USB-PD PPS >> power supply and they found the outputs were so far off what was >> requested that they ended up setting it to a fixed output and used >> another regulator for the final output. So not using the voltage >> programming ability of the USB power supply after all. I realised >> then that I was probably wasting my time - it's a standard for a >> perfect power supply, which might only be used to make >> barely-good-enough-to-sell power supplies. I shouldn't really have >> been surprised. > > Happen to have a link to the project? Or was it something you came > across ages ago? It was a while ago and if it's the one I found now in my bookmarks then it's not clear if they were actually using a PPS USB supply anyway. I've probably been mis-remebering again: https://tokarski.dev/posts/bench-power-supply-usb-c/ Likely it was just the limited specs of the PPS power supplies available in Australia put me off the idea, but that was probably at least six months ago so I should look again. This article describes charging Li-Ion cells by using a USB-C development/testing tool to control a PPS one: https://ripitapart.com/2022/12/31/directly-charging-li-ion-batteries-with-a-usb-c-pd-tester/ That does suggest their current regulation can't be relied on: "Although the PPS specification allows a device to set a maximum current level, my own testing revealed that there was too much variation amongst all my different adapters that I could not rely on the hardware to perform the constant-current regulation with enough precision for my liking" But it seems the voltage regulation from the ones he tested was acceptable. -- __ __ #_ < |\| |< _#