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Hi there,
so I‘ve been trying to create a custom bedside table with integrated USB C ports and LEDs (Attachment one), but I am kinda stuck on the ports. I‘ve ordered some cheap ones of ebay (link below post) and assumed that it would be enough to attach them to a 5v power supply, so I did (Attachment two). However my phone doesn’t charge and doesn’t seem to recognise the cable. I am using a 40w power supply and my phone can charge at 15w, so the amperage shouldn’t be a problem. I am kinda new to electronics, so my apologies, if this whole post is just me being dumb. I would really appreciate it, if someone has an idea about my problem.
Posted : 05/08/2022 12:49 pm
Guide to USB-C Pinout and Features - Technical Articles (allaboutcircuits.com)
How to Enable USB-C Power Exchanges With and Without Power Delivery - News (allaboutcircuits.com)
I would check these links out that go over the USB C spec. I am not certain, but since the ports on your nightstand will be DFPs they would need pull up resistors on CC1 and CC2. Your power supply is only 40W so you can't make all three 15W receptacles, but you could do two 15W and one 7.5W. (3A and 1.5A, respectively). Try putting a 10k resistor from CC1 to VBUS and from CC2 to VBUS. This will configure it as 3A supply.
Posted : 06/08/2022 2:06 am
TR47 reacted
USB-C is complicated, you have to configure the device as a master or slave, the simplest way is to get ones with a small resistor, it pulls down or up a pin to ground or positive(can't remember which) and tells the device on the other end which state it works in. You might also want to use separate power supplies for each port if you want fast-charge because devices have to negotiate the voltage through data lines, if you just use a splitter, it might raise the voltage for the device plugged in with data connected (laptop using 20V, for example) and fry the rest (old cellphone that should use 5V).
Read more on USB-C protocols or just go with USB-A, where 99% of the time, female end is on the master and outputting power
Posted : 09/08/2022 8:35 am
TR47 reacted
Topic starter
@tim Thanks for your advice, but I don’t really understand what you mean. Are you saying, that I should get different ports? I would like to avoid USB A, since most of my cables are USB C. I also get the problem with different voltages, but my devices all charge at 5V and the LEDs I want to use also run on 5V.
Posted : 09/08/2022 9:19 am
@tr47 Perhaps it would be easier to change the small PCB with the ports. Look for ones that that say they are configurable.
I just looked it up, it should be 56K to let your phone know there is no negotiating, this socket just provides a constant 5V. It is usually implemented into A-C cables so you needn't worry about it, but since you are using C-C, it wouldn't work without one. But I couldn't find one on Taobao, the biggest online market here in China where these things are made, which means there is probably no female port that has a resistor. You either have to make one yourself, which I am not sure whether it's safe to plug in other devices because they might accidentally be also programmed to act as power output and short the whole thing.
Best way to do this would be to have A ports for 5V only, and use extension cords for C ports with actual chargers that have a chip inside to control everything
Posted : 09/08/2022 9:37 am