4 ms·
More often than not these are usually cheap Chinese devices that are expecting a USB-C to USB-A (power-only) cable, because they're actually USB-A devices, with
by rrrrrrrrrrrryan 3mo ago
More often than not these are usually cheap Chinese devices that are expecting a USB-C to USB-A (power-only) cable, because they're actually USB-A devices, with USB-A circuitry, modified slightly to appear as if they're USB-C.
Basically they skipped out on building power negotiation smarts that are required to support real USB-C charging, and instead just swapped out the physical connector.
- Tharre 3mo agoThey skipped out on literally 2 resistors. That's it, that's all that is required for real USB-C charging.
- ACCount37 3mo agoYep. The two fucking resistors. All it takes 2 x 5.1K, and yet, somehow, people keep fucking it up. It's not expensive or complex. It's just that somehow, no one thought to look up "how to add type c to your device" online, or ask an LLM, or put literally any effort into making sure the device works as it should.
- philistine 3mo agoThose two resistors cost money. It's not incompetence. It's a deliberate choice.
- m463 3mo agoI've read countless stories of designs sent out getting backroom-cost-reduced by removing the most ridiculously cheap parts.
- Tharre 3mo agoYou're saving a fraction of a cent per device, while banking on customers not sending it back as defective because it didn't charge when they tried it with a random cable. If it is a deliberate choice, it's a really, really dumb one.
- myself248 3mo agoYup. Buy it, test it, post a review, return it. It's the only message you can send.
- kakacik 3mo agoIf it works (aka enough people buy it) it aint stupid
- pbhjpbhj 3mo agoCould not disagree more. Advertising is primarily about convincing is to buy things we don't need, don't want, or which are 'stupid' in some way. Half empty plastic packaging, especially the sort where the company spent money to [re-]design it to deceive people - stupid. It should be illegal. Near ubiquitous.
- klempner 3mo agoOne of my theories is that there is a deliberate choice happening by people who don't realize it is as simple as a couple of resistors and think they need some fancy PD negotiation chip. Even over on r/usbchardware it is super common for people to conflate "PD" with this missing resistor issue. Part of the confusion is that the devices that people want to charge with are very likely to be PD power supplies.
- mastercheif 3mo agoIt's because they take PCBs spec'ed for micro-usb and just replace the port with USB-C.
- pixelesque 3mo agoOut of interest, is that all that's required for the power negotiation handshake? I would have expected more complexity?
- nsvd2 3mo agoComplexity is cost.
- TomWhitwell 3mo agoJust two resistors to say ‘I am a device, give me 5V’ - you only need more negotiation = a chip - to get more than 5V
- pixelesque 3mo agoThanks!