4 ms·

Reflecting, this is quite off topic, but due to more voltages supported by USB PD, I thought I'd bring this up. A few years back, I really wished all the AC/DC

by iamchp 4y ago

Reflecting, this is quite off topic, but due to more voltages supported by USB PD, I thought I'd bring this up. A few years back, I really wished all the AC/DC converters for smaller home appliances would ditch the fragmented round pins, and go for a universal USB-A (at the time) standard. E.g. some fans, routers, my smart desk, my key light, etc. Perhaps we would be able to optimize better unified AC/DC converters. Perhaps it would be nice to think about something like this. Instead of having bulky AC/DC converters, go for single multi-port USB-C PD converters?

lazide 4y ago
It’s slowly happening - a great many small electronics have been transitioning to various USB connectors for charging (everything from bicycle lights to small drones). Those are all 5V though, which is great for typical one cell lithium, which is 3.7-4.2V, and where 500ma-2A is the most you’d need or want anyway. The issue so far is that for higher power levels or voltages the electronics are still complex and expensive, even with the PD standards, so it adds a lot of cost doing it that way compared to a typical barrel connector. Maybe in another 4-5 years and with some standardized and hopefully dirt cheap PD chips?
ohples 4y ago
I have a Home Pod mini in my kitchen which is powered via USB-C. Right now Its just using Apple's 18 w power brick. One of these days I mean to to install on of those mains outlets with built in USB-C ports: https://www.leviton.com/en/products/residential/usb-wall-outlets-chargers/usb-typec-with-power-delivery https://www.leviton.com/en/products/residential/usb-wall-out... It will eliminate a bulky adapter and let me use the plug for things that actually need AC, like my toaster or kettle. One wonders if it will start becoming common to have all plugs in newer/refab houses have these and they will be okay enough for most people. This is a little different then what your talking about, but both could be the norm. I imagine the form of what your talking about would be that power strips with a bunch of type - c ports on them (and maybe some AC) replace the power strips we use now.
- nordsieck 4y ago
  > One of these days I mean to to install on of those mains outlets with built in USB-C ports: I really wonder about those. I remember reading an article where someone tested a bunch of different power bricks and found that they really vary in quality. The cheap ones had really bad voltage sag and other problems. And they were an unsafe design (not enough separation between the AC and DC sides). Personally, I'd trust an anker or apple brick more than whatever lowest bidder device is in those outlets.
  - vorpalhex 4y ago
    And in a year or two when the standard changes again, you don't have a bunch of outdated ports hardwired into your house.
    - s3p 4y ago
      USB C has been around for some time, same with USB A. If you had both ports in your power outlet you'd have been set for nearly 20 years worth of peripheral charging.
      - boltzmann-brain 4y ago
        I don't agree. The past few years have seen steady growth in terms of power delivery. Devices have gone from 5V 0.2A which equates 1W, to 240W. That's a huge leap. Most older chargers are simply insufficient for more modern devices, but can still be used to power more conservative things like small desk fans, led lights, night lights, and the likes. You can repurpose an old wall wart by putting it somewhere else physically where you need it, but with an in-wall power outlet you'd need to replace the whole module every 1-3 years. The jumps in power delivery were drastic at times. However, now it's a good idea to go with these because it's unlikely power delivery for a lot of things will increase for a long while - see my other comment.
        svnt 4y ago
        It was ~4.5 W before, wasn’t it? With some off-spec supplies up to 4 to 5 amps or 25 W. This is still a big deal, but only one order of magnitude, not two.
sowbug 4y ago
Such a thing would have to be really smart about advertising power-delivery ability for each port without exceeding a total commitment of 1,800 watts (US 120 volts x 15 amps), but not actually needing an inefficient 1,800-watt AC/DC transformer, and then somehow still managing to be able to charge at least a couple high-power laptops simultaneously. All this to satisfy the reasonable desire to replace six bulky 15-watt transformers with one simple device. Contrast your typical $10 AC power strip, which lets you plug in 10,000 watts of hair dryers at once, because it's understood that a circuit breaker will (hopefully) blow if you do. It doesn't need to be smart. I think the basic problem is whether USB-PD allows a source to commit to delivering 100 watts to a port that asked for 20V/5A, but then notice that the port only needs 2 watts right now (because the device finished charging), so that it can reclaim 98 watts in its total power budget. So far I haven't seen a power supply that does this well.
- jasonjayr 4y ago
  Wouldn't that kind of overcommit be disastrous though? If a device was granted a 100W budget, but only needs 2W now, maybe it suddenly needs to burst up to the full 100W? If the hub reclaimed those other 98W, now it can't deliver what it promised, so something fails to work, or gets powered off.
  - sowbug 4y ago
    Depends on your definition of disaster. In the hair-dryer case, all six actually do turn on -- but only for a few seconds. The circuit breaker heats up and trips before the wires in the wall get hot enough to ignite the wood. Which sounds scary, but that's part of the design that enables normal spiky power usage of refrigerator compressors starting up, running a garbage disposal for a few seconds, etc., without constantly tripping a home's breakers. If USB-PD has some way for a single supply to "overbook" its commitments, then it could model this system. Otherwise, its competition will be people plugging lots of individual USB power supplies to AC power strips, which is bulky and wasteful, but extremely functional.
- deleted 4y ago
  [deleted]
boltzmann-brain 4y ago
Often you can convert things yourself. Back in the day USB only provided 5V, so anything that needed 12V still used a barrel plug wall wart. But nowadays you should be able to have simple breakout boards that negotiate PD to deliver the correct voltage (or correct "enough" that the thing can still operate, eg 14V instead of 12V). I've been converting some of my more problematic devices, for example here's a pretty clean conversion I did of my Wii U Gamepad back in the day. That was before USB C ports and cables were easily available, so I went with micro. USB C wasn't even a consideration back then. https://imgur.com/gallery/cx2gzxQ https://imgur.com/gallery/cx2gzxQ
- joshspankit 4y ago
  For anyone who wants to do this: it’s not that easy with PD. I have a dozen USB-C PD bricks of various brands. Only 3 of them properly provide 12v, and one of those only does it properly when there are no other devices plugged in to it’s 3 ports.
  - boltzmann-brain 4y ago
    Which is why you use a buck-boost converter if you want to get a specific voltage above 5V out of a usb wall wart.
    - joshspankit 4y ago
      I’m no electronics expert, but that seems iffy... Personally I would love to use USB-C PD for longer strings of 12V APA RGB LEDs as interior lights. In that case: not only is voltage a concern but also total wattage, heat, and long-term reliability. Is 60 or even 100W through a boost converter actually safe and easy?
      - fragmede 4y ago
        Boost converter's the technology and can be done as safely or as dangerously as you'd like. Waiting for a totally safe commercial product will take longer than DIY, naturally.

by iamchp 4y ago

lazide 4y ago

It’s slowly happening - a great many small electronics have been transitioning to various USB connectors for charging (everything from bicycle lights to small drones). Those are all 5V though, which is great for typical one cell lithium, which is 3.7-4.2V, and where 500ma-2A is the most you’d need or want anyway. The issue so far is that for higher power levels or voltages the electronics are still complex and expensive, even with the PD standards, so it adds a lot of cost doing it that way compared to a typical barrel connector. Maybe in another 4-5 years and with some standardized and hopefully dirt cheap PD chips?

ohples 4y ago

I have a Home Pod mini in my kitchen which is powered via USB-C. Right now Its just using Apple's 18 w power brick. One of these days I mean to to install on of those mains outlets with built in USB-C ports: https://www.leviton.com/en/products/residential/usb-wall-outlets-chargers/usb-typec-with-power-delivery https://www.leviton.com/en/products/residential/usb-wall-out... It will eliminate a bulky adapter and let me use the plug for things that actually need AC, like my toaster or kettle. One wonders if it will start becoming common to have all plugs in newer/refab houses have these and they will be okay enough for most people. This is a little different then what your talking about, but both could be the norm. I imagine the form of what your talking about would be that power strips with a bunch of type - c ports on them (and maybe some AC) replace the power strips we use now.

nordsieck 4y ago
> One of these days I mean to to install on of those mains outlets with built in USB-C ports: I really wonder about those. I remember reading an article where someone tested a bunch of different power bricks and found that they really vary in quality. The cheap ones had really bad voltage sag and other problems. And they were an unsafe design (not enough separation between the AC and DC sides). Personally, I'd trust an anker or apple brick more than whatever lowest bidder device is in those outlets.
- vorpalhex 4y ago
  And in a year or two when the standard changes again, you don't have a bunch of outdated ports hardwired into your house.
  - s3p 4y ago
    USB C has been around for some time, same with USB A. If you had both ports in your power outlet you'd have been set for nearly 20 years worth of peripheral charging.
    - boltzmann-brain 4y ago
      I don't agree. The past few years have seen steady growth in terms of power delivery. Devices have gone from 5V 0.2A which equates 1W, to 240W. That's a huge leap. Most older chargers are simply insufficient for more modern devices, but can still be used to power more conservative things like small desk fans, led lights, night lights, and the likes. You can repurpose an old wall wart by putting it somewhere else physically where you need it, but with an in-wall power outlet you'd need to replace the whole module every 1-3 years. The jumps in power delivery were drastic at times. However, now it's a good idea to go with these because it's unlikely power delivery for a lot of things will increase for a long while - see my other comment.
      - svnt 4y ago
        It was ~4.5 W before, wasn’t it? With some off-spec supplies up to 4 to 5 amps or 25 W. This is still a big deal, but only one order of magnitude, not two.

sowbug 4y ago

Such a thing would have to be really smart about advertising power-delivery ability for each port without exceeding a total commitment of 1,800 watts (US 120 volts x 15 amps), but not actually needing an inefficient 1,800-watt AC/DC transformer, and then somehow still managing to be able to charge at least a couple high-power laptops simultaneously. All this to satisfy the reasonable desire to replace six bulky 15-watt transformers with one simple device. Contrast your typical $10 AC power strip, which lets you plug in 10,000 watts of hair dryers at once, because it's understood that a circuit breaker will (hopefully) blow if you do. It doesn't need to be smart. I think the basic problem is whether USB-PD allows a source to commit to delivering 100 watts to a port that asked for 20V/5A, but then notice that the port only needs 2 watts right now (because the device finished charging), so that it can reclaim 98 watts in its total power budget. So far I haven't seen a power supply that does this well.

jasonjayr 4y ago
Wouldn't that kind of overcommit be disastrous though? If a device was granted a 100W budget, but only needs 2W now, maybe it suddenly needs to burst up to the full 100W? If the hub reclaimed those other 98W, now it can't deliver what it promised, so something fails to work, or gets powered off.
- sowbug 4y ago
  Depends on your definition of disaster. In the hair-dryer case, all six actually do turn on -- but only for a few seconds. The circuit breaker heats up and trips before the wires in the wall get hot enough to ignite the wood. Which sounds scary, but that's part of the design that enables normal spiky power usage of refrigerator compressors starting up, running a garbage disposal for a few seconds, etc., without constantly tripping a home's breakers. If USB-PD has some way for a single supply to "overbook" its commitments, then it could model this system. Otherwise, its competition will be people plugging lots of individual USB power supplies to AC power strips, which is bulky and wasteful, but extremely functional.
deleted 4y ago
[deleted]

boltzmann-brain 4y ago

Often you can convert things yourself. Back in the day USB only provided 5V, so anything that needed 12V still used a barrel plug wall wart. But nowadays you should be able to have simple breakout boards that negotiate PD to deliver the correct voltage (or correct "enough" that the thing can still operate, eg 14V instead of 12V). I've been converting some of my more problematic devices, for example here's a pretty clean conversion I did of my Wii U Gamepad back in the day. That was before USB C ports and cables were easily available, so I went with micro. USB C wasn't even a consideration back then. https://imgur.com/gallery/cx2gzxQ https://imgur.com/gallery/cx2gzxQ

joshspankit 4y ago
For anyone who wants to do this: it’s not that easy with PD. I have a dozen USB-C PD bricks of various brands. Only 3 of them properly provide 12v, and one of those only does it properly when there are no other devices plugged in to it’s 3 ports.
- boltzmann-brain 4y ago
  Which is why you use a buck-boost converter if you want to get a specific voltage above 5V out of a usb wall wart.
  - joshspankit 4y ago
    I’m no electronics expert, but that seems iffy... Personally I would love to use USB-C PD for longer strings of 12V APA RGB LEDs as interior lights. In that case: not only is voltage a concern but also total wattage, heat, and long-term reliability. Is 60 or even 100W through a boost converter actually safe and easy?
    - fragmede 4y ago
      Boost converter's the technology and can be done as safely or as dangerously as you'd like. Waiting for a totally safe commercial product will take longer than DIY, naturally.