Gadgetory

hello there i'm gary sims from android authority now back in the day the power that came out of your USB port was really quite simple it was running at 5 volts it gave out naught point 5 amps which means it gave you 2.5 watts of power and that was that however things have moved on significantly since then especially once you include USB power delivery so the question for us today is what is USB power delivery and how does it work well let me explain okay first of all let's get some terminology out of the way when we're talking about power we're talking about is watts and you calculate the Watts by multiplying the amps by the voltage so as I said just a few moments ago USB originally was five volts at naught point five amps so 5 times by naught point five half of five is 2.5 watts now the idea behind USB power delivery is a system where you can get up to hundred watts so from two point 500 Watts through a USB port now before we get into the details of USB power delivery let's look at all the different standards that come with USB and how much power each different standard allows a port to supply so starting with USB 2.0 5 volt naught point 5 amps 500 milliamps which gave you 2.5 watts of power now when USB 3 came along that 5 volts remain the same but it could actually provide up to 900 more point 9 amps of power which would give you 4.5 watts there's also a standard called the USB battery charging standard and we'll talk about that in a moment now with USB battery charging it's 5 volts at 1.5 amps which gives you 7.5 watts of power and then if you've got a USB type-c cable just connected to a USB 3 port then you can get 5 amp 5 volts at 3 amps giving you 15 watts of power but if you have a USB type-c cable connected to a USB power delivery system then you can get up to 20 volts 5 amps which gives you 100 watts now the key thing here to remember about power delivery is that it's the only one that changes the voltage level all of them including the battery charging standards still remain at 5 volts okay and there but power delivery can actually up that up to 20 volts now just mentioning quickly about the power battery charging standard that was basically a system that only works with charge as it doesn't work on computers that only works on charges and by shorting the data pins together because you can't transfer data over it the device that was charging could speak to it and realize that this is a battery charging compliant charger and therefore it could deliver up to 7.5 watts now all USB type-c cables are 3 amp compliant now the important thing to know about power is it only works over true USB type-c cables that means you go to USB type-c oval plug at one end and the USB type-c oval plug at the other end now you've got a cave with a type a at one and in a type C at the other and that cannot be used for USB power delivery and the reason for that is because USB power delivery actually uses some extra pins in USB type-c to negotiate the power level so what happens when you do have type a at 1 in and type C the other in there are some resistors in the plugs which tell the devices what type of cable this is now in the past has been a problem that people companies have been putting the wrong resistors in there and the result has been although the cable itself can support 3 amps what happens when you plug that into a device let's say like your PC into the motherboard and then you've got a phone at the other end that wants three amps it can actually say oh this is a three amp cable and it actually requests that three amps from your motherboard now remember of course USB normal USB is only up to anon USB type 3 is up to only naught point nine amps and that can actually cause your motherboard or your charger to overload that's why it's important these cables stick to the default power resistor configurations on them now as I mention what happens with USB type-c there's extra pins called the control pins that actually may talk to each other and through these pins they're separating the data pins separate than the power pins separate than the video pin they are there just to full control and what happens is the two devices when they've both got USB type-c can talk to each other and say hey I want this amount of voltage I want this amount of current and then they negotiate what they want now up until 45 watt even after 60 watts you a three amp cable is absolutely fine now if you're using something bigger than that then you're gonna have to go up to a 5 amp cable but anything from 45 60 watts in might in some cases we'll be able to use that 3 amp cable of course here we're talking about powering laptops with my powering monitors which I'm about powering things more than just your smartphone now the original pixel used a USB power delivery and I did a test just for this video just to confirm that power delivery worked very very well and that it was able to charge the battery from 0 up to a hundred percent in just 97 minutes just over an hour and a half which is great for a full charge but again that only works if you've got a USB the power delivery compliant charger and you're using a USB C cable with those USB C plugs at both ends now finally at the end it's worth talking about Qualcomm quick charge Qualcomm quick charge had a similar idea going on it was able to up the voltage more than 5 volts he could go up to 9 and 12 and so on and that was able to provide charge for phones now of course what actually happened is that that technically breaks the USB specification not technically allowed to do that and in fact Google make a statement about this in their Android compliancy document about what is a compliant Android phone or not let me read it to you We strongly recommend to not support proprietary charging methods that modify the voltage bus beyond default levels or alter sync source roles as such may result in interoperability issues with the charges or devices that support the standard USB power delivery methods while this is called out as strongly recommended in future Android versions we might require all type C devices to support full interoperability with standard type C charges so Google basically tried to say if you want to be called an Android phone you have to support USB power delivery and that's course what they've done with their pixel devices now at the moment it is still strongly recommended which is kind of their strongest language they could use without actually saying this is an actual requirement now that wording can be found in the in the androids seven compliancy document it can also be found in the Android 8 complaint a document so as of yet Google haven't forced manufacturers down this path but as they say they could do in the future now core coms response to this is actually for quick charge for quick charge for works side by side with USB power delivery and what that means is that if you have a quick charge for charger and you plug it into a power delivery device that say like a pixel then the the charge will recognize that it's not going to be using quick charge it's a switch over to using power to do so it allows both systems to run side by side and Qualcomm have done that in a hope that they can still sell their quick charge technology to manufacturers but still kind of remain compliant so that when you use your charger for other devices is still able to deliver the right amount of voltage and right amount of current and devices still work without suddenly staying on and this isn't quick charge I'll just resort back to 2.5 watts so actually that's a pretty good move from Qualcomm so in summary basically we're now hopefully moving towards an era of a kind of a universal power supply a situation where USB power delivery can be used to power monitors hard disks laptops charge up phones and as long as you've got that USB c-type cable at both ends then you'll be able to supply get in and the full amount of power be able to be taken and the good thing about USB power delivery is the consumer doesn't need to worry about the voltages and the amps as long as a charger says I support 45 watts or this charger support 18 watts then the USB power delivery system can kapkan talk between the two to actually deliver the right amount of voltage and an amp so basic if you were buying a replacement charge or we were at a friend's house you want to plug in something including even a laptop or even an external hard drive as long as it's USB type-c power delivery compliant and it's got the number of watts that you need from your original charger than that spare charger the replacement charger that one your boring will work exactly the same way so that gives us this kind of a universal power supply well utopia that we're all looking for well my name's Gary sim for under authority I hope you enjoyed this video if you did please do give it thumbs up please also subscribe to an Authority's YouTube channel hit that Bell icon so 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