Why Power Adapters Are So HUGE

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Why are external AC adapters often huge and unwieldy?
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Yours Grave
Yours Grave Day ago
Total shit.
chase vogt
chase vogt Day ago
Think they’ll ever just be built right into the wall outlets we use?
ArthursHD Day ago
In PC it does not make much sense cause for delivering 12 volts and high current you want short wire runs to avoid expensive cables or exse heat. Laptop/Phone PSU can be bought in an outlet as long as it's USB cause it is universal. The downside is that you don't have switch to cut off the power completely from PSU in outlet quickly for safety and efficiency.
NvrUseYur RealName
Love the outros on these! LOL!!
Rick Brannigan
Rick Brannigan 7 days ago
Great video
Abaqus 13 days ago
Linux distro comparison
Rowan Bird
Rowan Bird 20 days ago
0:50 Why do we have dual outlets when power bricks always block them
QuadraKev 22 days ago
but why do companies integrate the box into the plug instead of having a separate box
jhon doe
jhon doe 23 days ago
PA are NOT BIG ENOUGH!! we need PA for our phones!
w0ttheh3ll 24 days ago
"linear power bricks" are not a thing! WTF
soylentgreenb 25 days ago
It is unfortunate that single phase power is used. If that wasn’t the case you would always have a voltage higher than the low voltage DC you need. I think you’d only need the tiny capacitor after switching if that was the case.
Alex O'Dell
Alex O'Dell 25 days ago
The engineering but hurt...
Kris Wingert
Kris Wingert 26 days ago
4 diodes to make a bridge rectifier and the cap for a filter. Now you have dc. Simple. The next stages now involve dropping the voltage and regulating it for a stable output. The term switching really has no relevance to the 120v/220v input compatibility.
Cat Teenager
Cat Teenager 26 days ago
Did linus say that every power adapter has a built-in *FULL BRIDGE RECTIFYER*
Sina Madani
Sina Madani 26 days ago
"Smaller, lighter, more portable" I wish that were true for smartphones...
Landscape Guy
Landscape Guy 26 days ago
Linus you are a pervert.
Raizazel 26 days ago
Adapters are not built in out electronics for one reason above all, accidental electrocutions, imagine pluging and unpliging a cable at 220V from you phone/laptop every time you want to charge it good luck not getting fried doing that while you are just off of bed.
Recharge Games Studio
2000subscribers with no videos challenge
so when i will be able to fit my desktop psu to my suitcase
ricky v
ricky v 27 days ago
Personally, I've never made a big deal about power adapters. That's because power adapters are so huge that I don't have to. Anyway, good video. Very informative.
Rafael Cruz
Rafael Cruz 27 days ago
Bennet Fox
Bennet Fox 27 days ago
Did you start taking zoloft? You are not a spastic as you used to be which is nice. I just might start watching again.
BigBoy_fb 27 days ago
AC and DC hehe ACDC
ThatNoobVan 28 days ago
I’m extremely confused why there is a stock image of a baby sitting next to a psu and how they found it. Wtf.
Atharva Khanzode
Atharva Khanzode 28 days ago
Hey! Can laptop vacuum coolers damage the battery or the AC adapter? My laptop's AC adapter got damaged and I had to replace it . This happened after 5 days of using the Cooler. I have an MSI GL63 with dual side vents and dual back vents.
Nolimitscomedy 28 days ago
Linus really choked on this one. Hopefully an EE can transform his way of thinking.
Aj Meipalu
Aj Meipalu 28 days ago
Wait what's an 8 inch plug?
Jay Time
Jay Time 28 days ago
LOL i love it 'you could use a xbox360 PSU for a murder weapon' MORE MORE smart jokes
terminal2004 28 days ago
But they were HUGER.
Rahman Dh
Rahman Dh 29 days ago
can't play my old xbox 360 without this..
Deathcall 666
Deathcall 666 29 days ago
That intro laptop looked like my garbage Lenovo g50-70
Excel Cañete
Excel Cañete 29 days ago
Did you thought that the thumbnail of this video is a chese grater??
Narata 29 days ago
AC and DC current run off of Chuck Norris.
Thicc Doggo
Thicc Doggo 29 days ago
It would be more convenient for Apple chargers to be like laptop charger, so that that big bulky power supply can just go off to the side and the thing can be plugged into the wall outlet without interfering with anything
Mark Cerrillo
Mark Cerrillo 29 days ago
Teaching us about something they don't really know, classic LTT.
Trainboy1EJR 29 days ago
3:32 to 4:05 is all that needed to be said, AMPS + HEAT!
Tom Turnbull
Tom Turnbull 29 days ago
I spent 5 years in the seventies in a factory making switching power supplies for mainframes. These where about 24 inches long, 8 inches wide and about 6 inches tall and they weighed a huge amount.
Vita-Kyte Month ago
I get that it would be expensive, but wouldn't DC be better to use as the standard instead of AC, I'm sure we could get AC adapters but if we just changed to produce DC instead, we wouldn't need adapters right? (I know very little about this stuff so feel free to give me everything you got)
Kevin Crane
Kevin Crane 28 days ago
Short answer is : No
Keoki johnson
Keoki johnson Month ago
I didn't realize power adapters converted to DC - from Marvel 😂😂😂😂 But it makes perfect sense.
Michael Hinz
Michael Hinz Month ago
I’m an EE with 20+ yrs experience. Good video for a basic overview! Some of the factors that drive size are: 1: Safety (there are physical space requirements to keep the dangerous AC power away from the relatively safe DC power you might touch). Also we have to have minimum insulation to prevent things from accidentally wearing and electrocuting you. 2: noise. You touched on this. There are two kinds of noise Radiated (wireless) and Conducted. Radiated is dealt with by proximity (which you described), shielding, or careful filtering at different parts of the power circuit. Filtering almost always adds size and reduces efficiency (which makes heat) and is a difficult balancing act. Conducted noise comes to play with regulatory compliance. You don’t want your device making a lot of electrical noise on the AC line that can mess up other devices. Govt agencies (FCC, IC, CE) have limits on this noise level to make sure we all play nice. Again that means filters which can be quite large. The technology has improved a lot and today’s components are far better; however, there are some fundamental physics limitations that determine size of these parts. That being said, there is a lot of innovation and investment to produce more efficient and small power adapters. New methods are already drastically reducing the part count and complexity which makes my job as an engineer easier to meet challenging size and packaging desires. Again, great video! Thanks!
The Great Eldian Empire
Mine are 8 years and counting , wish me luck.
Jacob Dykstra
Jacob Dykstra Month ago
As an EE who is studying and designing switching power supplies I must say Linus is really pushing his boundaries with this one. Some of the information is correct but it is very misleading and you can definitely tell this video was put together with a few hours of research on Wikipedia or other similar sources by someone who clearly has absolutely no knowledge what's really going on. Please stick to what you know or hire someone with enough of a background to keep the video legitimate. I have seen linus do several videos like this now and they make me cringe.
Josh Guyette
Josh Guyette Month ago
What? Not watching, title thumbs down
LNCRFT Month ago
2:35 nice to see German/Austrian (probably a few more countries more) power outlets :)
John Suarez
John Suarez Month ago
Default Switched
If LTT videos 18:9 then why isnt Techquickie's?
OrdinaryGamer Month ago
I took my power brick apart and the board was wrapped in some plastic stuff witch was held on by a metal plate(p.s. I forgot to unplug it) and I was putting it back together and accidentally put the metal peice on first and it blew up xD
John Pekkala
John Pekkala Month ago
The compoents taking up most space are the transformer and the power smoothing condensers wich are often of the electrolytic cylinder type. A non switching power supply would need to be at least 5 to 6 times the sizee to handle the power. However being in a closed box without cooling most of these laptop psus are still on the limit wich stresses the compoents inside and also wastes power since they get really hot when they operate at their limit capacity. The one to my laptop for ex gets burning hot when working with things like rendering in Blender or different game engines like Unreal Engine wich I use a lot. It have not broken yet since it is rated for this computer but still, even its switching, components operating at their limits generate lot of waste heat wich decreases the efficiency of the unit.
soundslave Month ago
Do massdrop just sell headsets? It's all you guus promote from them
morten dybdal
morten dybdal Month ago
yeah linus i fucking love AC/DC !!!
TheModernFae Month ago
Hey Techquickie! I really like your videos. They really help me understand different aspects of tech. I've watched quite a few of your videos and don't think I have ever seen you talk about an EEG Machine. Could you do a video on EEG Machines and how they work? Maybe if through tech like this, reading minds could ever happen? I think this is a very interesting topic and would love to see a video about this on Techquickie. Thanks.
Damedsama Month ago
oh really? the transformer’s efficiency, in general, is in the range of 95 - 99 %
Jordan Fetherolf
It would've been cool if you'd mentioned gallium nitride power adapters that are just hitting the market. Anker has one that is smaller than m5ost cell phone adapters and can power a tablet or small ultrabook with much more efficiency than silicon...
klapausis Month ago
Power supply could be used as a murder weapon. Hmm... Sounds like a plan :D
Gonun Month ago
So much wrong in this video. Can't you just ask somebody with some actual EE experience?
Stuart Morrow
Stuart Morrow Month ago
0:53 The circuit diagram at 0:53 only makes the current non-negative, it doesn't actually flatten it out.
Hey, the adapter from the acer aspire 1 is very small and after 20 minutes of heating up it cools rapidly bown... And it is fucking cool
Edgar Granados
Edgar Granados Month ago
To convert AC to DC you need a center tapped full wave rectifier, jk lol. Use a Full bridge instead
Edgar Granados
Edgar Granados Month ago
Electrical Engineers
Carvin0 Month ago
Wouldn't it be great if power bricks could at least conform to a standard on the DC side: voltage/current/plug. That way you could carry just ONE. And there'd be a big enough market to incentivize someone to develop and sell a really well-designed model instead of the cheap designs we all suffer with.
Campo87 Month ago
More resistance, more juice (current). Oof, what is ohm's law?
Spike Spike
Spike Spike Month ago
My gaming laptop charger is huge, but as long as I can play my games safely, I don’t mind carrying it.
Valeri K.
Valeri K. Month ago
Guys, I love your videos, but this one you really rushed and didn't do enough research. ALEX you are the engineer who is supposed to check this! There are lots of inaccuracies and way too simplifications. There are tons of engineers watching your channel and you could ask for suggestions for relevant information.
ModeZt Month ago
Zero tech details
Anita SV
Anita SV Month ago
Real reason: We run house in AC, why not rectify once for entire house and be done with it.
supernova gamer
supernova gamer Month ago
Power supply too bulky? Then call upon the one hero who can fix it, THE RECTIFIER!
taltigolt Month ago
i wish they made power supply powerbricks imagine a pc with no powersupply just a huge power brick?
Doom2pro Month ago
You should see my 330W Gaming Laptop adapter...
Lord Takahashi
Lord Takahashi Month ago
Better? I don't knoooow... *(Looks at Xbox One Power Brick)*
android272 Month ago
I don't mind having to lug a large brick everywhere. What I mind is having the wide up the cables so that I can put it in my laptop bag. I could just quickly shove it into my bag but I don't like doing that as I have other things in there. I don't know if there is a solution but I want to find something that makes winding up my cord a lot easier.
TheRandomGamer Month ago
The power brick you show is the same as my laptop wadafak?
Hank Month ago
As a side not, SMPSs themselves ARE extremely efficient (depending on the operating conditions). The bulk and power consumption mostly comes from first rectifying the mains power, then cleaning up the output of the switching regulator itself. In regards to bulk, transformers are commonly used on the mains side to both isolate the device and bring down the cost and size of the rectifying components. Additionally, the more power required, the larger (both physically and in terms capacitance/inductance) inductors and capacitors you'll need to smooth out the pulsed output of the controller.. That's why your phone's charger (just look at the kindle's 5V adapter) can be so tiny while performance laptops have bricks that really earn the name. In regards to inefficiency, as I mentioned, rectifying the signals is where most of this is lost. First of all, SMPSs are DC-DC converters, IE, they need a DC signal to function, so the AC signal needs to be rectified.To rectify an AC signal, you will typically use a bridge rectifier consisting of rectifier diodes. For the most part, they have extremely low on-state resistance, so that can mostly be ignored. However, they do have a threshold voltage which must be overcome before they begin conducting. P=IV, where P is power, I is current, and V is voltage drop across the device. Even if the material used to create the diode is a super conductor, that threshold voltage will remain, and the power consumption of each of the diodes will be directly proportional to the input current. The rectified sine wave then needs to be smoothed out via capacitors. The higher the voltage input, the lower the losses in the diodes, but the cost and size of the components needed to rectify, smooth, and convert that high input skyrocket as well. Then, the output of the switching controller driving the converter is essentially a pulse-width-modulated signal, so it switches between 0V and the input voltage at a certain rate. That is then connected to a capacitor, inductor, and dioede configured for the specific use case required for the application (do we need a higher output, lower output, or both?). The more power draw required, the larger the components will need to be. Finally, as you mentioned in the video, there are RF concerns. While part of that has to do with the conversion process itself, there is also the issue that no matter how large the output inductor and capacitor that you use are, there will be some ripple in your output. I.E. it's not very clean power. For sensitive electronics, that's a problem. To get perfectly clean power, you'll need to go back to the linear converters you mentioned at the beginning. They typically consist of a zener diode and a resistor. When the voltage is above the reverse threshold of the zener diode, it will conduct to pull enough power to drop the voltage down to that threshold voltage, and the "missing" voltage is dropped across the resistor. To increase the efficiency, you will want to select a linear regulator that is as close as possible to the bottom of the ripple voltage without risking some other phenomena that I won't address here. That concludes my TED talk. Thank you all for coming.
The Universe
The Universe Month ago
title isnt >why power adapters are dummy thicc SOILED IT
Tchitchouan Inouane
Tesla was right, damn you edison
Thomas farquhar
Thomas farquhar Month ago
hey, have a pocket sized laptop! With a *B O X*
Benjamin Harrison
Fun fact- I was actually sent to the hospital after receiving a traumatic brain injury from an Xbox power supply being used as an improvised weapon.
Nikolas Sehman
Nikolas Sehman Month ago
110volts? What country uses that? The Edison plug that it is labeled with is used for 120volt in the USA
Pentium100MHz Month ago
Another reason why some devices do not have internal power supplies is that if the device plugs into the wall, it needs to be certified for safety before you an sell it. Certification costs money and it is cheaper to certify the external power supply once and sell multiple devices that can use it. That being said, I dislike when a device with no batteries has an external power supply. I also prefer linear power supplies or at least power supplies with 50Hz transformers (the voltage regulator after the transformer can be switch-mode) because they are easier to repair than switching power supplies. And cheap PC power supplies with Active PFC (and crappy high voltage caps) have a very annoying failure mode where the power supply blows up and trips the circuit breaker. Now you have to turn the circuit breaker back on to get your other devices working again.
Kerr Month ago
Oh my god nobody has ever used a linear power supply to convert mains to 12v! nobody sane anyway! linear power supplies are more for 5v to 3.3v type of stuff. A linear power supply converting 120v to 12v would be
Jhonyrod Month ago
Switched mode power supplies get their name because they operate by turning on and off the power and varying the duty cycle (and sometimes frequency) in order to keep the output at a specific point, kind of like how a PWM (pulse width modulated) signal can be used for DC motors speed control. Actually, the simplest SMPSs are DC-DC, not even AC-DC. Input voltage has nothing to do with the mode of operation!
Randomii666 Month ago
Well... Regarding the X360 power brick, the Xone one is as big too
Caden Epp
Caden Epp Month ago
you had so much potential to make an ACDC joke, but you didnt im sadd
NsD Fake
NsD Fake Month ago
ac dc
zodiacfml Month ago
Massive misinformation. You could have asked a competent electronics guy for a few minutes to make this video. The size of the power adapters has nothing to do with AC-DC conversion. LED light bulbs have AC to DC converters internally, thus, small size. The size is dictated by the WATTAGE and DC output quality of the power supply/adapter. Laptops require huge adapters as they are sized/watts for simultaneous charging and use of a laptop. If your laptop charges very slowly while you use it, it means you have a small/weak power adapter
sitcommander Month ago
>move to solar panels on roof >Store the generated dc current in batteries >Directly use the dc current. 0 ac/dc conversion, zero electricity wastage Why isn't this a thing?
Daniel Auen
Daniel Auen 28 days ago
It can be, it's just easier to convert to ac.
R D Month ago
So nice not to have that obnoxious and loud intro at the start of this video. I'd actually stopped watching these because of it, but I decided I'd give this one a bash and skip ahead... Was nice not to have to do that.
Jake M
Jake M Month ago
This is still an area that tech companies can push. Apple doesn’t use external power bricks in their iMac’s or Mac Mini’s, and their laptop bricks are still fairly small. As phone chargers need bigger and bigger power units, and laptops chargers are increasingly becoming lower and lower wattage - I think we’ll see a point where the units combine and we just use USB C cables directly into the wall. Apple is almost there at the moment in that they recommend their 29 watt wall charger for both the iPhone and one of MacBooks, but hopefully this becomes more widely used by other manufacturers as well.
Twinrehz Month ago
AC? Or DC? *WHY NOT BOTH??* **Runaway train....**
sapphireblue88 Month ago
I thought this video would be about Gallium Nitride power adapters! =/ Making this video outdated dare I say...
Daniel Andrade
Daniel Andrade Month ago
1:39 "Wong, you're invited to my wedding!"
Richard James
Richard James Month ago
Mohammed Abdullah
Because Optimus Prime is in the power brick
Richard Crim 3
Richard Crim 3 Month ago
You know power adapters of today are BS because manufacturers could really use two diodes to to convert from 120 volts AC to 120 volts DC and then a down step Transformer to convert 120 volts DC to 12 volts DC😔
urmamasllama Month ago
something I wonder about. why don't we just use one giant switching adapter for a whole home or one per breaker? then you just need a step down converter in the device and you're done without having to deal with the massive bricks everywhere.
David Thattenbanos
It annoys me when people with little electrical knowledge explain electrical subjects.
panzer vor!
panzer vor! Month ago
Linus is too onions to lift an AC-DC adapter
Melkers Teknikhörna
Xbox 360 power supply in the thumbnail is very big in real life
Michal Canecky
Michal Canecky Month ago
This video is bunch of nonsense. You have absolutely no clue what are you talking about. You are embarrassing yourself. Just delete the video, consult an expert, create a new one.
Cujo Month ago
-->-- Your best friend
SoulGaming Month ago
Stop roasting the xbox360 power brick
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