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Comment by jaywalk | Hacker News Reader

USB-PD requires extra circuitry that barrel jacks don't. I doubt we'll see the end of barrel jacks.

Technically yes, but not really. The only requirement is two $0.001 resistors on the CC lines, giving you 500mA @ 5V. You can get up to 3A @ 5V simply by measuring the voltage the charger puts on the CC lines, so that can be done in $0.05 in parts.

Getting the full 5A @ 20V experience is possible with a chip costing less than $0.50, so even that isn't too expensive.

Reference, please? Everything I see that does standalone UFP (upstream facing port) PD winds up costing a LOT more than that.

The Cypress/Infineon chip that does this is around $2 and requires quite a bit of external circuitry: https://www.digikey.com/en/products/detail/infineon-technolo...

OTOH, a lot of things have stopped including transformers, so the tradeoff might be worth it for the manufacturers.

Exactly, the dc-dc bricks should more than offset the USB C costs.

there's enough cheap parts floating around now that offer standalone conversion from USB-PD to raw DC voltage. if customers are preferring USB connections, OEMs will find a way to implement it.

something like this is no more difficult to implement than a barrel plug https://www.aliexpress.com/item/1005005315614647.html

I took a few of those USB-PD decoy boards and soldered them to some universal power jacks. Now I have a home kit that can power any legacy barrel-jack devices. I did have to label each cable with the hard-wired voltage so I don't mix them up.

Basically a DIY version of this: https://www.aliexpress.us/item/3256804001423573.html

maybe for the truly cheapest products, but USB-c PD chipset can be pretty cheap these days.

Barrel jacks already have extra circuitry in quite a few of them. Dell is notorious for this; if you use a non-Dell charger it won't even let you charge your laptop.

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