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Classic article.

I recently got a 30W Anker USB-C charger that is as small as the really old iPhone chargers, less than an inch cube, and it charges my M1 MacBook at full speed. It's far less than a third of the size of this 90W charger.

I'd love to see a teardown of that, too.



> it charges my M1 MacBook at full speed

MacBook Pro models are able to fast charge at 140W (M1 onwards). Even the original M1 MacBook Air can charge at 45W[0]. I don't think it's accurate to say that the 30W Anker charger can charge your "M1 MacBook" at "full speed".

0: https://www.reddit.com/r/macbook/comments/kdpxmm/psa_m1_macb...


Well what do you know, the M1 Air shipped with a 30W charger, despite at least one point of the charge cycle being able to handle 45W.


There are a few video games I can play with my m2 laptop plugged into my 80W monitor and the battery still charges. But it will drain on the 60W monitor if I get the wires switched around.


On the other hand, not every MacBook is a MacBook Pro.


In my comment I wrote just three sentences. The middle sentence starts off "Even the original M1 MacBook Air..." Then the link I provided is to an investigation on charging speeds of the MacBook Air.


That link shows that it's using >45W while (potentially) powered on and doing things other than charging.

Apple supplies a 30W charger in the box, so I think it's fair to say that a third-party 30W charger is "full speed" (in the sense of "as good as the stock one", if not full speed in all potential scenarios GP might or might not care about).


Full Speed to me means as fast as the laptop will allow, not as fast as the one that came in the box.


That is not a reasonable definition of full speed. You would seriously say out loud that a 45+W charger “charges the laptop 50% faster than it charges at full speed”?


No, but in some context I might call 30W "full speed" and 45W "turbo speed" ;)


Apple supplies cheaper macbook pros with a less than full speed charger.

When iPhones shipped with chargers they were only 5w despite being able to charge from faster chargers.


The trick is GAN technology:

https://www.promate.net/blogs/blog/what-is-gan-technology

Half of my company has done the same and mostly Anker too. I got the charger/battery combo, as it is amazing for travel.


The internal organization is also an interesting point. They keep the AC and DC sides air gapped so that no shenanigans can happen in a dying PSU.


Aren't primary and secondary still connected for EMI management (causing the "weird buzzing sensation" when touching metal parts of connected devices)?


About a quarter of the way down there’s a section called, “The charger's underside: many tiny components” picture with a red line on it. Below it talks about it and claims only optoisolators connect the two sides. Obviously the transformer also connects the two sides, but you know what I mean.


Hmm, then where is that stray voltage coming from that's definitely present (in my experience) on non-grounded MacBook chargers?

I think that's what the Y capacitor does (also pictured in the article): https://www.vicorpower.com/resource-library/articles/back-to...


I don't have an answer to that question, only an educated guess. But I gave up on getting it a long time ago. I use the three pronged connector unless I'm plugged into something like an inverter.

Before that change I did end up throwing away a PSU that was causing tingling on my laptop. I don't know if that's a manufacturing flaw or damaged wiring.

The educated guess as to the mechanism is 'floating ground' (the white wire has a potential versus earth ground). It causes weird behavior in house wiring, particularly ones that have had iteration in their wiring (remodels, additions). Then there's the one where LED lights turn on even if the switch is off, but I think that's a separate phenomenon from floating ground.


It’s inherent to all class 2 PSUs (or really all PSUs without mandatory safety grounding, which is only safely possible as a class 2).

It happens even in a properly wired building without faults, since a class 2 PSU needs a path for EMI on the secondary side to be dissipated, and due to the lack of a dedicated ground, the only choice is to connect both phase and return to the secondary circuit via a Y capacitor.

A common downside of that is a stray voltage of up to half your mains voltage on any conducting surface of your device, but it’s harmless since it’s not capable of sustaining any meaningful current.


It's sad that for such high price you have this "weird buzzing sensation" (which is because it is not grounded properly), and that you can hear the buzzing sound too if you put your ear very close.


By definition you can't have grounding on a power supply without a grounding pin, unfortunately.

Apple's power supplies for MacBooks do have a grounding pin, but the default duckhead adapter they ship with usually doesn't leverage it, so you end up with a class 2 power supply and the buzzing sensation.

> that you can hear the buzzing sound too if you put your ear very close.

I've found Apple power adapters to be pretty good in that regard, unlike some third-party power supplies that I can hear across the room. If I can only hear the noise when I put my ear next to the supply, I can just not do that :)


GaN is great for carrying weight and volume.


> as it is amazing for travel.

Do the Anker one's come with international plugs? I didn't see any indication on their product pages that they come with the adapters. Nor could I find them for sell.


Get one with the “figure 8” cable connection and then get a figure 8 cable for your destination.


I do like the form factor of the Anker. I was a little surprised that they don't come with international adapters. My Genki Switch charger does and it looks like they have a similar, removable plug adapter.

Oh well, I'll probably follow your advice or checkout a different brand. Thanks!


I’ve got this one here, along with a couple of country specific power cables:

https://www.anker.com/products/a2046?variant=42448630612118&...


The term you are looking for is C5 connector.


That may be what it’s called, but I never use it. Ironically I work closely with electronics engineers and we still use “kettle lead”, “figure 8” and similar in person since everyone knows what they mean. BOMs are a different kettle of fish of course.


I like “Mickey mouse cable” for C5.


[flagged]


That is not the case. Fast charging is worse for the battery, but a 60W GaN vs a 60W SiC charger is not going to treat your battery any different, for example.


The concern about chargers being 'good' or 'bad' for your battery is mostly an issue with 90s and 00s technologies where chargers directly interfaced with batteries. The way modern PD devices work, however the battery charges is entirely up to the onboard charge controller in your device. They always charge in accordance with how your device was designed to charge. We call them 'chargers' but really they're just power supplies.


GaN is just the transistor technology, how does that translate to bad for batteries?


It's not the GaN, it's the higher wattage that's possible. Fast charging can increase device/battery temperature which, for fan-less designs like iPhones or MacBook Air, can lead to slightly higher degradation.


That's not correct and very misleading. The wattage is the max amount of power the charger can output. It's up to the device being charged to negotiate and pull the right amount of current and wattage. This is case with modern charging protocols and even older 5v usb chargers. This is similar to how you might have a 15A rated outlet in your house, but that doesn't mean it's going to "force" 15A though whatever device you plug into that. It's the device that determines how much power it will pull.


My analogy is an EV - of course your EV isn't going to pull current that's dangerous but fast charging it has been shown to degrade battery life - especially if the EV doesn't have active cooling for the battery pack.

Putting that EV on a slow charge that might be sufficient for an overnight charge might be better for the battery pack.


This is a setting on the device side. The EV it self will decide how much current to pull, based on charging profile that you set.

You are correct on that charging at higher currents can reduce battery cycle life, but it's the device it self that decides how much current to pull based on the charging profile that you selected. In your example with an EV,you set the charging profile on your vehicle, not the outside charger. The charger's job is to provide as much current/voltage as requested by the device.


You are correct, but the comment didn't say "fast chargers," it said GaN.

Here is a (very cute) 35W GaN charger. This would be considered fast charging for a phone, but not for a laptop. https://sharge.com/products/shargeek-retro-35-gan-charger

It is just plain inaccurate to state that GaN is the problem, or opens up new possibilities for fast charging. All it does is make the charger smaller.


For the uninitiated, can you explain like I’m five? Why are GaN chargers worse?


What makes them not as nice for your battery?


I’d love to know why GaN is bad.

As far as I understand electronics between the AC electricity and DC device make more of a difference


I believe this is misinformation and probably should be flagged.


Apple is now using GaN for chargers as well. Here's a teardown of Apple's 70W charger: https://www.youtube.com/watch?v=lYfoRkzqAII


Erm, comparing a 30W charger to a 90W charger is a bit like asking why your local UPS driver doesn't do a day's work in a VW Golf.

Wattage aside, I'm sure there's more to it than meets the eye. Afterall, Apple are not stupid, smaller charger means less plastic casing and less packaging means simpler manufacturing ... no doubt the Apple ones are the size they are for a reason.


> no doubt the Apple ones are the size they are for a reason.

That reason might well be "because it's slightly cheaper to build a larger charger and most people wouldn't be willing to pay more for a device that comes with a compact one in the box".


Apple are so large and require such scale and control that they have to phase in technology like GaN over time.

You can't just order 15M components, built to a custom spec, and get them reliably overnight. Hence Apple have been working to scale supply lines, work with suppliers (and their suppliers) and ensure both quality and other factors (like environmental concerns).

Anker can go out of stock and then produce again when things stabilize. Apple can't stop selling Macs for 3 months without a major global crisis.


Also people just like smaller chargers.

Source: have a HP laptop with a brick-size power brick.


You can get a third party GaN charger if your laptop supports charging over USB-C. Most recent Pro- and Elitebooks do.


>I recently got a 30W Anker USB-C charger

After getting the M1 I'm typing this on I asked if a MagSafe 1-MagSafe 3 adapter existed. <https://np.reddit.com/r/applehelp/comments/10duooq/i_want_a_...> I felt foolish when I realized that being able to charge from USB-C meant that I could use any old charger and a USB-C cable for the times when I'm away from the stock Apple charger that came with the computer. Bonus: No more dealing with the Apple cable to the MagSafe 1 plug that inevitably lost its sheathing and exposed wires within a year.


Been pretty happy with my GaN Anker brick, which is 150W and smaller than not only the 87W Apple brick, but also the 140W Apple brick and can charge up to 4 things instead of just one. It packs into my laptop bag nicely and makes it unnecessary to bring any other bricks.


> can charge up to 4 things instead of just one

Mind that a lot of chargers do weird power allocation things when multiple devices are connected. You probably aren't going to get all 150W to the laptop with four devices connected; depending on the charger and what port you're connected to, you may get much less.


Yeah, it’s almost always at night while I’m asleep that it’s charging multiple things. It also has a port marked to plug a laptop into, which I’d assume it prioritizes over the other ports.


I always bring just a ~5 year old 65W Dell USB-C charger. It can charge my Pixel from 0 to 100 in 90 minutes, and can take my M1 Pro from 40% to 80% in 60 minutes. It is rugged, and significantly smaller than the Apple power brick that came with the M1 Pro.

Don't think I've travelled with more than one charger since phones switched away from micro-USB.


Worth noting that Anker's 150W charger[1] isn't quite as fast as the 140W Apple charger, because the Anker will only deliver up to 100W to any single port (even if it's the only one being used) whereas the Apple can pump the full 140W out.

Of course, outside of fairly niche situations, this isn't going to make a practical difference to your life. :D

[1]: https://www.anker.com/products/a2340


I can't tell from the article the dimensions of that charger they are tearing down, but the article is from 2015.


ChargerLab does a lot of charger teardowns. Not sure which 30W Anker you were referring to, but here is one:

https://www.chargerlab.com/teardown-of-anker-30w-usb-c-gan-5...


Like reaperman said, I don't know about "full speed". But for a year I used a 27W charger with my M1 MacBook Pro. It wasn't fast, but did the job (especially overnight).


How is it charging as fast as a charger 3 times more powerful?


I think only the M2 air (and M1 pro, depending on size) can use fast > 30W charge; it varies by model.


No, even the M1 air can charge at 45w, which is a good bit faster than the 30w adapter they ship with it.


Only for a relatively small portion of the batteries charging curve. The real advantage is when charging while turned on.




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