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Comment by chx | Hacker News Reader

So... https://www.tindie.com/products/clarahobbs/pd-buddy-sink/ like this, right?

Now, I saw a ThinkPad plug in the blog post. Lenovo sells this ready made. ttps://support.lenovo.com/us/en/accessories/acc500104

Search for 4X90U45346 to find purchase links. Two ideas:

US: https://www.cdw.com/product/lenovo-usb-c-to-slim-tip-cable-a...

Elsewhere: https://www.ebay.com/itm/Usb-C-To-Slim-Tip-Cable-Adapter-NEW...

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> So... https://www.tindie.com/products/clarahobbs/pd-buddy-sink/ like this, right?

Note all the extra electronics on the PD-Buddy-Sink, which OP specifically calls out: "Chips like the popular FUSB302 which only provide the wire level handling of the USB-PD protocol, require a lot of software work to make them reliably operational. And that software will need to run on a µC which adds to BOM." You can see the large STM32F(!? way overkill) on the PD-Buddy.

The STUSB4500 OP used allows for a much smaller, fully-integrated solution.

Only 45W, so OP’s will work better for large laptops, assuming there are big thinkpads using this connector (I have no idea if that’s the case)

I think 45W was the max for laptops and the larger supplies shipped are for driving Docks.

That being said ... Newer Lenovo Laptops come with 65w USB-C. The Docks however still use Slim Tip and go up to 90w. So Idk.

The slim plug is available on adapters from 45w to monster 230w (that RTX 5000 in the P53 alone eats 110W, the CPU is nominally 45W but in reality it's oh-my-god then there's a screen to power, typically 4K and we didn't even start charging our battery, previously only the 17" laptops needed 230W at full config, the basic adapter is "only" 170W). The plug center leg is for wattage detection, there's a resistor to ground and the size of the resistor tells the laptop how many watts can it draw safely.

Yeah I like the cable solution better for a laptop, but this device could be used for anything! It would be cool to have it power an electronics breadboard too, especially if you can get both 20V and 5V off the same charger cord.

I knew about the cables on eBay but wow, didn't know about Lenovo's official one. Thanks!!

Also the other project is pretty cool as well. Will check out the components there too.

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