USB Power Explained (USB Power for Dummies!)

welcome back dprv tv viewers it's chris nichols here and you've just caught me charging my olympus om-d e-m1 mark 3 off of a power bank as you can imagine we always have a lot of cameras to charge so hang out with me and we'll watch this camera charge this is entertaining content right this is what you came for does a watched camera charge it does actually but is it boring so why don't instead we take this time while this is charging to try to demystify this whole concept of usb chargers wall adapters different protocols and will it or will it not charge your camera properly because as simple as it might be to just think oh if cable a fits into slot b everything should be a magical experience and unfortunately like all things in life it's a little bit more complicated than that now before we go any deeper i just want to talk about some of the terms that you're going to hear today we're going to be talking about volts and amps and watts and uh i'm no electrical engineer i just want to keep this nice and simple but when we talk about wattage the higher the wattage coming through a usb port generally speaking the faster it will charge things or the more powerful devices it will be capable of running okay now to work out your wattage you take the volts and you times those by the amps so just to give you guys an example this particular power bank has an output that will do 5 volts at 2.4 amps now if you do the math that equals 12 watts of output now what about milliamps well it's a very easy conversion a thousand milliamps equals one amp so you could say that a port outputs 0.9 amps or 900 milliamps it would basically be the same thing but what about capacity well if you ever look at a power bank battery or battery on your camera you'll also see a milliamperes per hour kind of rating now that's fairly easy to understand if this is a ten thousand milliamp hour battery that means that if i had something that was drawing ten 000 milliamps of power this should roughly power it for an hour now how we use this when we're charging batteries for example this is 1720 milliamp hours in this battery and this is 10 000 milliamp hours in this battery so if i charge i should be able to get just over five of these batteries fully charged off of one of these so our brain hurts already but let's keep going so next we have to talk about usb ports and usb protocols now this is your classic rectangular usb type a port it's comforting it's familiar and this comes in a lot of protocols so let's talk about older stuff usb 1 and usb 2 protocols i mean one's defunct now it's gone 2.0 you might find as the lowest common denominator but the thing to keep in mind here when it comes to charging a usb 2.0 port can only output 5 volts up to 500 milliamps 0.5 amps now this then got upgraded to usb 3.0 and this you might still find on a lot of laptops and a lot of devices usb 3.0 can up that amperage to 5 volts at 0.9 amps or 900 milliamps but it doesn't end there i mean all these protocols keep getting updated remember we're not talking about compatibility or data rates we're just talking about power charging so then usb 3.0 got another specification called usb bc battery charging spec 1.2 and this then let it put out 5 volts up to 1.5 amps and then usb 3.2 came out and that raised it even higher now we can do 5 volts at 3 amps i mean that's 15 watts of power and that's fairly substantial if all this sounds confusing that's because it really has been a confusing ordeal over the years luckily though we now have a new port which you've probably seen usbc now one of the first advantages here is you can't plug it in the wrong way because i'm sure we've all been there where we take a usba port and we try to put in an upside down and then the computer says that's not it and if you push really hard it'll go in but it's not pleasurable for anybody and you're gonna break some so luckily usbc makes things a lot easier in regards to how we plug it in but it has its own set of complications now it's important to understand that usbc simply refers to the shape of the port it has the potential to transfer a lot more power than older style usbs but when it originally came out it basically was the same as usb 3.2 and that's the setup that we have going here charging this camera this created confusion because when we then had something like the canon mirrorless line of cameras and we were on a press trip trying to get these charged with our power banks well we took the same cable which absolutely fits we pop it in there off of the same power bank putting out 2.4 amps nothing charging so what gives well the fact is manufacturers want to make more powerful devices that have higher energy requirements but still have the convenience of charging or powering over usb-c cables laptops are really good example of this and so they had to come up with a new protocol and they came up with pd or power delivery this dramatically raises the output potential i mean you can go up to now 9 volts 15 volts 20 volts and if you've got the right certified cables you can go from that 3 amp limit now up to 5 amps that's 100 watts of power as a maximum potential now this is a really interesting protocol because here let me just give you an example let's say you take a pd rated charger but you take an older device uh like this olympus camera for example well the pd rated charger is going to start out at a very low voltage and amperage that will be compatible with legacy devices but let's then say i take a pd rated device like this can in here and i plug it into that same charger now the two communicate with a handshake protocol they figure out how much energy they actually need to draw and then they draw it so this leaves us with two very important points to consider first off pd rated charging devices are very universal and will work like any standard charger on older devices that's a huge plus but if you have a device that needs a pd-rated charger and you don't have one so what are some good examples as a photographer of where that might be an issue well all the canon mirrorless full-frame cameras the r the rp the r5 the r6 they need pd rated chargers or a lot of the modern nikon so the z5 the z6 ii the z72 and the z9 they're also requiring pd-rated chargers it's important to keep in mind that camera manufacturers are not very forthcoming about what's compatible and what isn't compatible with their cameras they really want you to buy their original manufacturer chargers so when in doubt sometimes all you can really do to make sure is plug in a charger and see if the light comes on okay so we know that we want a pd-rated unit but how do we know that we're buying one well that's where it gets a little bit complicated as well and you really got to look at the fine print i mean often we are looking for the letters pd on these devices just to tell us that but we can also look at some other clues looking at this power bank we can see we only have one output voltage listed 5 volts at 2.4 amps whereas typically pd-rated charges will give us multiple voltage options and multiple amp options and so this is not a guarantee but a very good clue that this power bank is not pd-rated you can also see the next power bank same thing just the one output listed this simply has twice as much capacity as this one has but then we take a look at this wall charger i bought and now there's a few clues on the back here i can see pd that's nice when i look at the output though that's my real clue there now i'm getting different options 5 volt 9 volt 12 volt 15 volt and 20 volt up to 3.25 amps so i know that this is a pd rated charger and when i also look at the unit itself on the usbc ports look at that i do get some letters pd so those are all good clues that at least that would support what i'm looking for now while we're on the topic of pd chargers i'm holding two different wall chargers in my hands these are both pd-rated chargers now this one here is for a smartphone it doesn't say pd anywhere on it because i don't think the manufacturer really intends for you to charge anything else with it other than the phone but it is indeed a pd-rated charger however it can only output 18 watts of maximum output it does work with the canon eos r5 but this wall charger that we've already looked at this does have many more options for output it'll go up to 65 watts so this should charge the camera faster assuming that the camera will make use of that extra wattage but just keep in mind although they'll all work they don't necessarily put out the same amount of power and they don't even sometimes label things the way that you might want them to i also want to mention cables because unfortunately they're not all created equal now here's the good news every single usbc cable will work with a power delivery charger but basic cables will only work up to three amps you have to make sure you've got certified cables that will let you go up to 5 amps we haven't really found a camera that that's been a problem with but if you're trying to power your laptop you're probably going to need a special high wattage charger and the right cable we've also found other devices like cf express card readers that needed the 5 amp certified cables so i guess long story short when you do buy these make sure that you buy the right ones for your needs don't throw them all in a box together mix them up and think you can just grab any one and make sure it works because they're often not even going to be labeled in any way to tell you whether they're certified or not and that can be a real headache now as an alternative to a power bank or a wall charger you can use your laptop or desktop to charge a lot of your devices but you still have to check those ports and their specifications so this particular laptop here isn't that old and it has a usbc port on the back but it's not pd-rated so it will not charge this canon eos r5 unfortunately but my new laptop here has a thunderbolt 4 port now thunderbolt's a different protocol altogether but it uses the same connection and those ports are pd-rated jordan also has thunderbolt on his apple laptops and charges cameras with them all the time works great so if you are shopping for a new laptop or desktop computer and having some of those ports is going to be important to you make sure that you check that out before you buy them all right so i want to leave you guys with a few takeaways now first off jordan and i were making our show we use a lot of devices that are usb chargeable microphones cameras smartphones and honestly for the most part a lot of those devices are pretty flexible and how they'll charge if i can find any adapter and the right cable they're usually going to work maybe not the fastest that they're capable of charging but they are certainly flexible but we're going to see more and more devices coming out that are going to require pd-rated chargers so if i was going to set up another charging station at home a place where i can plug in all my batteries and get everything going i think it makes a lot of sense to spend the extra money get pd-rated chargers get good cables and know that they'll work on all your new devices as well as your old devices now what about those good old-fashioned external wall chargers for your camera batteries well they still absolutely have a place i mean if the manufacturer includes them for free in the box that's a great bonus you know that they're going to work with your battery type it's usually very easy to find a wall plug maybe not the fastest charging solution but i still think these have a place but usb charging is just so much more convenient especially when jordan and i are using multiple cameras from different brands it's nice to just be able to use the same charger to charge all of them instead of having to manage a whole bunch of these and keep track of them as well usb charging opens up not just faster charging for camera batteries but also the option to even power the camera while you're using it off of usb power and that has a lot of interesting applications as well so i hope this video really does clear up some stuff for you but keep in mind we've only just scratched the surface here and there's other things we could get into like data transfer rates uploading and downloading speeds different cables and how they affect that whole business and if that's something you're interested in well let us know in the comments below and then we might look at tackling that in the future otherwise go to dpro.com there's always great educational articles there to learn from please like and subscribe to the channel we'd appreciate that we'll see you guys soon for another episode of deep review tv [Music] you

Channel: DPReview TV

Views: 162,026

Keywords: usb power, usb power bank, usb power adapter, usb power delivery, usb power supply, usb pd explained, usb c pd explained, pd power, pd power bank, pd power delivery, pd power charger, usb power for dummies, usb charging for dummies, usb charging, usb power for cameras, how usb power works, what is pd power, what is usb pd power, usb power limit, how to compute usb power, how to calculate usb power, usb cables for charging

Id: cqR_bwJi_e4

Length: 12min 17sec (737 seconds)

Published: Wed Dec 01 2021