frontpage.
newsnewestaskshowjobs

Open Source @Github

fp.

Open in hackernews

USB Power Delivery: Plugging into the Benefits

https://www.aptiv.com/en/insights/article/usb-power-delivery-plugging-into-the-benefits
17•mooreds•3d ago

Comments

edent•1h ago
I've basically stopped buying any portable electronics unless they take USB-C.

Currently travelling with a laptop, watch, toothbrush, eReader, camera, bug-bite treater, and phone - all charging from the same power brick.

I'm guaranteed of getting a replacement cable / charger wherever I am in the world if I need it.

The only slight snag is some cheaper itema refuse to use PD and insist on plain 5V/2A - buy most decent travel chargers have NON-PD ports.

Amusingly, most of the buses I've taken recently also have USB-C ports on them for ad hoc charging. Perhaps one day EVs will use USB-PD-Max rather than CCS :-)

ElijahLynn•1h ago
Same!

I've also returned a few USB devices that ship with a USB-A to USB-C cable and ONLY charge in that mode, they also MUST charge with USB-C PD.

The two so far were a therapy light and some Zippo hand warmers. Like, who in the hell would design a device that has a USB-C port on it where only a fraction of chargers will work on it. It feels even worse than proprietary charges, because you see a USB-C port on it and think, oh I have a plug that fits it, and then it doesn't F**ing work. Idiot engineering/product teams, making the world suck with their falsely advertised USB-C ports. If anyone of you are on a team that ever makes this decision, just know that it is a stupid decision, and jump ship when you can.

myself248•55m ago
The thing is, making a 5v-only device PD-compliant is literally one resistor. It costs well under a penny.

It's pure ignorance, not a decision, but the lack of one. Lack of caring, lack of having an actual engineer involved, just slapping an oval-shaped port into a product where a trapezoidal port had been, and blindly thinking that magically makes it spec-compliant.

Or not thinking about the spec at all.

I return these devices too. Lots of them. My e-commerce returns over the last year are probably 50% PD non-compliance, 50% all other defects combined.

exmadscientist•19m ago
It's two resistors, actually. But they cost $0.0003 each (that's 0.03¢, or just around 3,333 of them for US$1) from distributors. Though there appears to be a bit of a stock crunch right now.

So... yeah.

The bigger issue is not really the parts cost, it's the fact that it adds an extra part to the design that has to be purchased and tracked and assembled and blah blah blah. This is the real reason it often gets left off on the bottom-of-the-barrel products. Many times there is no other use for a 5.1kΩ resistor. And it might not even fit well at the cheap sizes (0603 or 0402), and going down to 0201-capable assembly factory flow just for these two resistors is not going to happen.

megous•15m ago
Only if the device's consumption is < 2.5W, which is what a USB 2.0 computer USB-A's data port limit is. Anything above that, compliance gets a bit more involved and complicated.
helterskelter•6m ago
There's an otherwise decent shortwave radio out there that was originally charged with a micro-usb, then they released a "new" USB-C model...except it will only charge with a 5V brick because they literally just swapped out the ports. Really annoying.
MrBuddyCasino•43m ago
You can always use a „PD Decoy“ if the voltage is USB compatible. A 5 / 9 / 12 / 15 / 20 Volt barrel plug is trivially USB powerable.
mcsniff•42m ago
I'll bite. What type of watch do you have that has a direct USB-C port on it?
ianburrell•36m ago
I think you are confusing the devices with USB-C that require USB-A, and devices that charge the standard USB-C 5V/3A/15W. The USB-A ones cheaped out in including the resistors that signal legacy USB mode, they work with the ones in the cable or adapter.

Lots of people assume that USB-C always uses USB-PD, but the basic signalling is done with resistors. Lots of devices only need 15W, and it is better than USB-A charging. If you want faster charging, buy more powerful chargers.

m463•13m ago
For travel I have a bunch of cables with adapters on the end (choose usb-c, lightning, micro-usb). Can use usb-c, but have the ability to use the others.

It has helped out in a bunch of unexpected situations (usually someone else's device)

blacksmith_tb•8m ago
I'm hoping we'll see most e-bikes at least use 240W usb-c pd charging (I figure I have about a decade until I will wish I had some assist and buy one, so probably by then, they'll have gotten there...)

I also have assorted products that won't charge c-to-c (some from respectable manufacturers even, like Philips), but I see you can get little adapters with 5.1K resistor you plug into said crappy devices to cover that, I will have to try some out.

hazkoulia•1h ago
I'm looking forward to USB-C PD small format factor PC's. A decent amount of room in the PC cases is taken up by the power supply. And if USB-C could somehow provide a range of voltages to the motherboard, SFFPC's could be downsized even more
omh•49m ago
There are some SFF PCs that can take USB-C power.

Lenovo have some,but sometimes require adapter cards. And a few of the Chinese N150 units will take PD power

It's great for hot swapping and more portable than a laptop.

exmadscientist•29m ago
> And if USB-C could somehow provide a range of voltages to the motherboard, SFFPC's could be downsized even more

You reeeeeeally don't want to do that. Cable inductance is a big deal, among other issues. You want the main DC-DC regulators on the board, usually right at the load, for the main loads. Most of the PSU bulk is for dealing with mains itself: handling 50/60Hz or mains isolation is just physically large. Getting in secondary 20V DC (or so) from a single connector and then regulating it down on board is pretty much the ideal solution.

(I can't even begin to comprehend the horrors of a USB-PD negotiation involving multiple voltages. It's already the worst standard I've ever had to deal with.* Don't make it worse!)

(* Not hyperbole, it is truly, truly awful. At least things like 60601 are bad because, you know, they're covering lots of stuff like lifesaving medical devices. USB-PD is... holy hell, it is just bad.)

Animats•34m ago
240 watts over a USB-C connector? What next, USB toasters and coffee pots?
dotancohen•23m ago
That's only a single ampre at standard European mains voltage. It's still a lot of power for those tiny connectors and insulation, but an order of magnitude insufficient for those appliances.

I bet that cable gets plenty hot at 200+ watts.

m463•12m ago
I remember scoffing years ago at USB powered coffee warmers. Maybe the situation has changed.
smallmancontrov•33m ago
Speaking of which, does anyone know a line of PD Decoy modules to convert barrel jacks to USB-C without the atrocious behavior of "oh, the charger doesn't have 12V, here's 9V have fun!" that the early ones all did? Ideally I'd like a little red light to come on or something, but I'd settle for not silently browning out the device.
miladyincontrol•24m ago
iirc theres ones that do. However I dont recall there being any clean fix to the amperage constraint issues. Especially when a lot of usb-c chargers will vary output as they heat up with usage.

Which is kinda part the issue, usb-c charging bricks, they aren't usb-c power supplies, there is no expectation of sustained output capacity. Thankfully at least some the multiport ones have renegotiation more or less solved cleanly rather than what is essentially rebooting the PD controller.

m463•10m ago
sounds like someone needs to create a DC-DC charger
simoncion•48m ago
> I've also returned a few USB devices that ship with a USB-A to USB-C cable and ONLY charge in that mode...

By "that mode", do you mean "1.5A @ 5V" permitted by BC, or do you mean "3A @ 20V" permitted by non-type-C PD?

> Like, who in the hell would design a device that has a USB-C port on it where only a fraction of chargers will work on it.

Who in the hell would design a charger that can do Type-C PD but can't do either pre-Type-C PD or BC? Does the charger in question also shit the bed when a USB 1.0 device attempts to draw 100mA @ 5V? I hope not! Were it me, I'd return that crappy thing for a refund.

duskwuff•19m ago
> By "that mode", do you mean "1.5A @ 5V" permitted by BC

Neither - OP means devices with missing CC resistors which will fail to charge with a compliant PD source. (The A-to-C cable works because it provides 5V Vbus unconditionally.)

exmadscientist•17m ago
The A-to-C cable often does not work because the resistors are supposed to be in there.

So if you are having complete charge failures, try a different cable.

megous•7m ago
A-C cable assembly always works, CC signal is connected within the cable to Vbus via 56kOhm resistor, but that's only relevant to the downstream port, not to the upstream USB-A power sourcing port which does not have access to the CC signal. Upstream port provides power unconditionally within some limits depending on port type (CDP/DCP/USB3.0/2.0 data port/...).

Show HN: Kage – Shadow any website to a single binary for offline viewing

https://github.com/tamnd/kage
122•tamnd•2h ago•32 comments

Rio de Janeiro's "homegrown" LLM appears to be a merge of an existing model

https://github.com/nex-agi/Nex-N2/issues/4
182•unrvl22•4h ago•104 comments

Chaosnet

https://tumbleweed.nu/r/lm-3/uv/amber.html
8•RGBCube•27m ago•0 comments

Firewood Splitting Simulator

https://screen.toys/firewood/
435•memalign•4d ago•151 comments

Not mine, but it's a website where you can use a segment display

https://aresluna.org/segmented-type/
29•unexpectedVCR•3d ago•3 comments

Ask HN: What are you working on? (June 2026)

70•david927•3h ago•286 comments

Perlisisms

https://www.cs.yale.edu/homes/perlis-alan/quotes.html
65•tosh•4h ago•33 comments

Caddy compatibility for zeroserve: 3x throughput and 70% lower latency

https://su3.io/posts/zeroserve-caddy-compat
107•losfair•5h ago•34 comments

The Birth and Death of JavaScript (2014)

https://www.destroyallsoftware.com/talks/the-birth-and-death-of-javascript
180•subset•7h ago•107 comments

Formal Methods and the Future of Programming

https://blog.janestreet.com/formal-methods-at-jane-street-index/?from_theconsensus=1
108•eatonphil•7h ago•29 comments

The only scalable delete in Postgres is DROP TABLE

https://planetscale.com/blog/the-only-scalable-delete
82•hollylawly•3d ago•38 comments

Lisp's Influence on Ruby

https://blog.tacoda.dev/lisps-influence-on-ruby-6a54f1a7740e
180•tacoda•3d ago•28 comments

FarOutCompany

https://faroutcompany.com/
72•bookofjoe•5h ago•10 comments

No, everyone is not using AI for everything

https://gabrielweinberg.com/p/people-are-consuming-ai-like-they
321•yegg•4h ago•335 comments

I indexed 669 GB of my GoPro videos using my M1 Max computer and local ML models

143•iliashad•4h ago•31 comments

USB Power Delivery: Plugging into the Benefits

https://www.aptiv.com/en/insights/article/usb-power-delivery-plugging-into-the-benefits
18•mooreds•3d ago•26 comments

Rome Fell and Nobody Noticed

https://friedkielbasa.substack.com/p/rome-fell-and-nobody-noticed
49•fkozlowski•1h ago•2 comments

Show HN: Dual YOLOv8n UAV Detection on RK3588S at 42 FPS Using NPU

https://github.com/alebal123bal/khadas_yolov8n_multithread
44•alebal123bal•5h ago•7 comments

Linux 7.1

https://lore.kernel.org/lkml/CAHk-=wi4BF4bMhZNZ1tqs+FFV4OuZRe3ZqdWB+LxRLmRweUzQw@mail.gmail.com/T/#u
126•berlianta•3h ago•20 comments

Show HN: 3D print Z reinforcement via injected loops

https://mgunlogson.github.io/magma/
35•mgunlogson•5d ago•10 comments

Global density and biomass of arbuscular mycorrhizal fungal networks

https://www.science.org/doi/10.1126/science.adu4373
32•zdw•1d ago•2 comments

Rio de Janeiro's city government model Rio3.5 beats Qwen3.7 in recent benchmarks

https://twitter.com/zenmagnets/status/2065796012820848699
120•lucasfcosta•5h ago•31 comments

How to earn a billion dollars

https://paulgraham.com/earn.html
300•kingstoned•7h ago•837 comments

Quivers: A year of linear algebra by drawing arrows

https://lisyarus.github.io/blog/posts/quivers-a-year-of-linear-algebra-by-drawing-arrows.html
20•ibobev•4d ago•3 comments

Free SQL→ER diagram tool, runs in the browser, nothing uploaded

https://sqltoerdiagram.com/
320•robhati•15h ago•63 comments

How did Atari apply side art to Arcade Cabinets?

https://arcadeblogger.com/2026/06/14/how-did-atari-apply-side-art-to-arcade-cabinets/
58•msephton•6h ago•16 comments

Honda Civics and the Evil Valet

https://juniperspring.org/posts/honda-evil-valet/
372•librick•18h ago•89 comments

A 'cold blob' in the Atlantic could be a sign of AMOC shutdown

https://www.cnn.com/2026/06/12/climate/cold-blob-atlantic-amoc-ocean-circulation
146•tambourine_man•5h ago•192 comments

Dillo directory – Directory of useful sites that work reasonably well on Dillo

https://dir.dillo-browser.org/
31•HotGarbage•2h ago•0 comments

KPMG pulls report on AI usage due to apparent hallucinations

https://techcrunch.com/2026/06/13/kpmg-pulls-report-on-ai-usage-due-to-apparent-hallucinations/
97•Brajeshwar•5h ago•16 comments