{"id":73103,"date":"2025-01-11T20:01:11","date_gmt":"2025-01-12T01:01:11","guid":{"rendered":"https:\/\/pappp.net\/?p=73103"},"modified":"2025-01-13T20:17:15","modified_gmt":"2025-01-14T01:17:15","slug":"usb-c-trigger-boards","status":"publish","type":"post","link":"https:\/\/pappp.net\/?p=73103","title":{"rendered":"USB-C Trigger Boards"},"content":{"rendered":"\n<p>Between having more disposable income and the potential for upcoming trade weirdness, I&#8217;ve been pretty fast-and-loose about buying random bullshit that catches my fancy from China of late.  <br \/><br \/>A recent Aliexpress order consists mostly of USB tampering supplies, like an exhaustive set of breakouts for all the common USB connectors, including a couple extra type C breakout boards because I&#8217;ve been doing a bit of Chromebook abuse recently and a <a href=\"https:\/\/chromium.googlesource.com\/chromiumos\/third_party\/hdctools\/+\/HEAD\/docs\/ccd.md\">SuzyQ cable<\/a> is likely to come in handy.  <br \/><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"575\" src=\"https:\/\/pappp.net\/wp-content\/uploads\/2025\/01\/HW398-1024x575.jpg\" alt=\"Close up of a HW-398 USB C Trigger Board\" class=\"wp-image-73419\" srcset=\"https:\/\/pappp.net\/wp-content\/uploads\/2025\/01\/HW398-1024x575.jpg 1024w, https:\/\/pappp.net\/wp-content\/uploads\/2025\/01\/HW398-300x169.jpg 300w, https:\/\/pappp.net\/wp-content\/uploads\/2025\/01\/HW398-768x432.jpg 768w, https:\/\/pappp.net\/wp-content\/uploads\/2025\/01\/HW398-1536x863.jpg 1536w, https:\/\/pappp.net\/wp-content\/uploads\/2025\/01\/HW398.jpg 1662w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p><br \/>In that batch, I also picked up a 10 pack of these little <a href=\"https:\/\/www.aliexpress.us\/item\/3256806810933610.html\">HW-398 USB C PD trigger boards<\/a> (aka Decoy boards).  They have a USB C Female connector on one end, + and &#8211; pads on the other, and a series of little pads marked with voltages that you can solder bridge to an adjacent resistor to have it negotiate that mode &#8211; apparently via any of the PD\/QC\/AFC protocols for doing so. <br \/>They seem like they should be useful for powering projects from easily obtained junk, but merit investigation because they also seem a little sketchy and were a whopping $0.63\/each. <br \/><br \/>A couple of the behaviors and design decisions are interesting:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The USB C connector is slightly inset on the PCB, which is probably good for strength, but rather unfortunate for mounting it into a project. <\/li>\n\n\n\n<li>They DO supply 5V when none of the higher values are selected, which is both reasonable and desirable.<\/li>\n\n\n\n<li>There is a little blue indicator LED next to the plug, and it&#8217;s marginal at lower voltage.<\/li>\n\n\n\n<li>It appears if you set a voltage not supported by a supply, you get the next voltage down, which I gather is suggested by the standard. This is not unreasonable but has real potential for unwelcome surprises if you don&#8217;t protect your design. The most likely issue seems to be a lot of supplies don&#8217;t support the optional 12V mode: I didn&#8217;t thoroughly test, but I popped one strapped for 12V onto a little Anker 313 whose label says 5V@3A,9V@3A,15V@2A,20V@1.5A and it delivered 9V.<\/li>\n\n\n\n<li>The IC is conspicuously unlabeled.  It&#8217;s an SOP10 package, and is smart enough to do to necessary USB negotiations (which are actual USB protocol traffic performing a handshake to read and write some control registers at either end).  A little googling seems to imply the chip is a <a href=\"http:\/\/fastsoc.com\/wp-content\/uploads\/2022\/05\/FASTSOC-FS312-datasheetv1.4.pdf\">Fastsoc FS312<\/a> &#8211; It&#8217;s in the right package, supports PD,PPS, and QC negotiations, which lines up with the product description, and the setting straps are connecting resistors of values 184(180k\u03a9)=20V, 140(14\u03a9)=15V, 104(100k\u03a9)=12V, 513(51k\u03a9)=9V which matches the datasheet.<\/li>\n\n\n\n<li>I haven&#8217;t done any load testing, but I don&#8217;t see any sign of regulation on the board, so I suspect the regulation will depend entirely on the supply. <\/li>\n\n\n\n<li>I have no idea if the USB IF considers these legitimate. <\/li>\n<\/ul>\n\n\n\n<p>It certainly seems like a useful gadget for the parts bin.   LCSC doesn&#8217;t seem to stock the FS312 IC, which is a shame since now that I know they seem to just work with the very minimal suggested circuit in the datasheet that requires only a capacitor and resistor beyond the chip and connector, I&#8217;d start designing them into boards if I could get them stuffed by the usual scumbags.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Between having more disposable income and the potential for upcoming trade weirdness, I&#8217;ve been pretty fast-and-loose about buying random bullshit that catches my fancy from China of late. A recent Aliexpress order consists mostly of USB tampering supplies, like an &hellip; <a href=\"https:\/\/pappp.net\/?p=73103\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,37,1,10],"tags":[],"class_list":["post-73103","post","type-post","status-publish","format-standard","hentry","category-diy","category-electronics","category-general","category-objects"],"_links":{"self":[{"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/posts\/73103","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=73103"}],"version-history":[{"count":0,"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/posts\/73103\/revisions"}],"wp:attachment":[{"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=73103"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=73103"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=73103"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}