At my work, we have an X-ray machine for PCB reverse engineering. On Fridays we throw in random stuff from around the office, and sometimes make videos about what we find inside.
A few weeks ago we released an X-ray teardown of several other, older chargers. Very interesting to compare with these fancy new ones!
The best part I find about ChargerLab teardowns is identifying all the passive and discrete components.
Western distributors tend to only stock western/japanese brands of these, but they can make up a sizable fraction of the BOM (especially electrolytic capacitors) so knowing who the big players are comfortable with using is very handy. LCSC stock a lot, but its nice to know which suppliers have been proven in use.
> but its nice to know which suppliers have been proven in use.
Watch out. Some of the suppliers you’ve never heard of are capable of delivering good parts to companies like Apple but still have ultra cheap parts available retail.
Hopefully Apple releases a UK version of this adapter soon. The design looks very similar to my beloved Apple UK 20W charger [1]. I’d buy a 40-60W version in a heartbeat!
Are you sure of that? For years now I think Amazon and Apple have an agreement where only Apple or Apple-approved third-party vendors can sell Apple products on Amazon?
Wow, that does look very neat for an Apple charger. The prongs are individually foldable, right?
I wish there was something like this for Europlug chargers. Ironically, the most compact USB adapter for me so far is one with a US plug, combined with an US-to-Europlug adapter, which can be made very compact, but seem a bit risky at 220V, given that US plugs expose the prongs while connected.
On the U.K. plug, the pins are linked by a mechanism to the earth pin, to prevent the user from plugging it in without the earth pin too - so foldable en masse, rather than individually.
> "Wow, that does look very neat for an Apple charger. The prongs are individually foldable, right?"
Better than that. You just move the biggest (earth) pin and the other pins fold automatically with it (in the opposite direction!), via a perfectly weighted/sprung mechanical linkage. It's a very smooth, elegant, robust action. Whoever designed it should get some design awards!
Please do not save money by using unlisted electrical equipment. Spend the extra $20 for a product that is tested and listed by UL/CE/ETL, it’s not worth burning a building down over $20.
You couldn’t pay me enough money to plug this into a building’s electrical distribution system, it’s drawing ~3A at 120V (60W at 5V plus inefficiency) and in a very small form factor, I sure hope the engineering and QA of that $5 charger is up to par. Did they include an internal fuse or did they forego that to save $0.03? Who knows!
I wonder what temperature this thing hits. I have an even smaller 65 W GAN charger[0] that gets pretty toasty under load. I can't really see Apple wanting to ship a toasty charger, though.
I remember the old macbook pro chargers, they and the cable would get so hot it melted the insulation of the cable (over time). Not to mention the self-desoldering GPU’s inside the actual laptops.
I don't think it was heat melting the insulation, blame the TPE used reacting. Anyways thread from the last time Apple charger stuff was discussed: https://news.ycombinator.com/item?id=28054090
I had 2 cables that melted like this. I eventually bought the newer version with a different insulator. Used with the same charger and same laptop, but no melting.
Wow, that's really small. Only 43 cm3 (without the plug) for the EU version. I own an a Anker Nano II 65W GaN Charger and that's already small with 64 cm3. I can imagine that Rolling Square one getting even hotter with that low amount of material, and thus cooling.
The one thing I like about the Apple charging bricks is how on certain models the prongs can be swapped out for a cable, which is very useful when the wall plug is cramped. However, this device doesn't seem to incorporate that so I'm not sure what benefit it has over an Anker.
Is there a way to slow down these high power chargers? Sometimes I want a fast charge but mostly I want slow to getting hot. I realize overnight charging phones are smart enough to do this but otherwise seems to be impossible without having two different chargers.
The charging smarts are always in the phone, and always have been. Just because a USB port has 15 or 30 or a gazillion Watts available doesn't mean that the phone is required to consume that much. Similarly, the wall outlets in your house may be able to supply a couple of thousand Watts -- but that doesn't mean that a device plugged in is required to use all of that.
And batteries can charge pretty fast these days. Modern pocket supercomputers keep track of battery temperature to keep things within defined limits during charging.
AFAIK the real problem, longevity-wise, for these batteries in normal use is the time spent at extremes of charge (<20% or >80%, ish).
That all said: Sure, some phones have options.
My Samsung phone does some man-behind-the-curtain tricks to attempt to make it reach 100% just before it predicts that I'll unplug it (eg, when I wake up). The idea is to maximize the charge on the phone while also keeping it at 100% SoC for as little time as practical. This probably works great for people with regular schedules (which is to say: people who are not like me).
This phone also lets me explicitly disable various fast-charge modes. I think there's at least two different modes that I can turn off (but I leave them all turned on).
And there's also a mode that limits the maximum charge to 85%, to promote long-term battery health. I have this mode engage automatically when using wireless charging, which is something I only do with the wireless charging cradle on my car's dashboard. (I do want the phone to be powered while I drive, but I don't normally need anything to work extra-hard to cram that last 15% into the battery when I'm on a long drive. It's a good balance, for me.)
It's up to the device. If I have an alarm for the morning my pixel 7 slow charges over the night so that it's full when the alarm goes off. Modern charging standards give all the control to the client device.
Is that with a dock, or without? My Pixel showed me a menu of choices for how to behave when first shown its wireless charging dock (charge to full ASAP, assume we'll need to be charged by alarm time, and some others) but I agree that a device can choose to do this from any power source, I don't feel like it gave the same choice when plugged in to a wall, maybe I'm wrong or it's in a menu somewhere.
You could convert from USB-C to USB-A and back. MicroUSB adapters are popular to chain for devices that only charge on USB-A. There are also adapters just force legacy USB charging for same problem devices. Then your phone will only charge at 12W.
On newer MacBooks you can turn on a similar battery protection mechanism to the phones. I believe vs the phones the smaller chargers won’t stress these cells since they’re a lot larger. 20-40W into a 15Wh battery is more stress than the same through a 52Wh (MBA) battery. A 1C charging rate is healthy.
The device being charged controls the charging current. Typically for smaller gadgets, a single resistor connected to the charge controller IC sets the current. Bigger things like laptops may be more sophisticated.
USB-PD now has a standard for having sink devices request a particular current from the charger, meaning that you could actually remove a converter from the sink device side, because with a programmable source, the current limiting happens on the power supply side. Cool stuff especially for small electronics like wearables.
Generally though if you want to charge with USB-PD and accept all kinds of chargers, the sink device will have to have its own charge control PMIC.
All this negotiation happens over a side band via the "CC" pins on the USB-C connector.
I still keep a few 5 watt chargers around and use them for overnight charging whenever possible. I reserve the use of high power chargers for the odd occasion when I need the speed.
Probably wearing your batteries out more. Bunch of studies done have found fast charging causes no additional degradation. Unless you hold the charge below 90% or something letting them dwell at 100% for hours is worse.
I use USB-A ports on a dumb charger, but most likely, it'd be best for the battery to use a charger with PPS support (programmable power supply - the device can request finely tuned voltages, reducing losses and thus heat inside the device).
On my Samsung S24 Ultra I have a routine set up where it automatically disables fast charging during the night, but enables it again during the day - the logic being that I don't mind if the phone charges slowly while I sleep, but if I plug it in during the day then I probably want the quickest top-up possible.
I wish they'd discount their 35W dual port chargers or that I could find a similar 3rd party charger.
My main criteria are (1) dual USB-C ports to charge multiple devices in one location, (2) compact enough to not block the other receptacle, and (3) ports face down/to the side so can fit between the wall and furniture. Unfortunately most chargers fail at least one of these.
This isn't exactly what you're looking for, but it may fit the use case.
I've recently been replacing some of the wiring in my house as part of a renovation, and I discovered that Leviton sells outlets with PD USB-C built in now! Not talking about the useless 2A USB-A "built-in" chargers of yore, now they actually have proper PD up to 60W!
They do also sell non-PD, so it requires some careful checking of the model numbers. And the 60W one is pretty large (the in-wall part) so it might not quite fit in an existing wallbox if it is a small one. But briefly:
- T5636: two USB-C PD, up to 60W total / 60W individual or 30W each if both in use
- T5635: two USB-C PD, up to 30W total / 30W individual or 15W each for both
- T5634: one USB-C PD and one USB-A. USB-A is 10W and USB-C is up to 50W (even if both are in use)
They also make T8xx versions of these that have 20A receptacles (NEMA 5-20R) but those are harder to find.
They also make other T56xx/T58xx which have non-PD USB-C, good for places like bathrooms where shavers/etc work fine on 5V.
I've found that putting a few of these around has eliminated a lot of the Anker chargers I used to have sticking out everywhere. They're completely in-wall and they leave both outlets free. If I need 100W for my computer, I'll still use a separate charger, but otherwise these are fine.
The only point they don't hit on your list is the ports facing down, but because they're flush at the wall, that means they don't interfere with furniture (any more than having any plug plugged into the outlets at all would).
If you're in Europe/elsewhere, not sure if other manufacturers make similar devices. I know Legrand makes some 30W PD ones in the US market, and as they're French, maybe they make them for others as well.
I might use these in my basement remodel since I can easily install deeper boxes. A right angle connector cable would also solve the issue of the port direction.
This is very cool, I might actually get one to charge my laptop.
That being said...
I can't be the only person who consciously avoids fast-charging my phone. My whole apartment is full of wireless charging pads intentionally plugged into weak chargers (wireless charging avoids putting wear on the USB port). 60 watts can't possibly be healthy for a battery small enough to fit into a phone.
Wireless charging may avoid putting wear on the USB port, but it typically does negatively impact battery health due to higher heat while charging. I suppose with a sufficiently low power charger this may not be a factor, though.
You aren’t, but that concern is mostly superstition.
I work at a place with a huge phone fleet. We have interns study our telemetry and records because I kids like phones and they find ways to save us money. We allow for low friction replacements of phones at 12 months — the average replacement is ~27. The most common issues are cracked screens and excessive scratching on iPhone 16 and a Samsung I cannot recall. Batteries are only an issue for field devices subject to excessive cold or heat.
Unless you’re trying to keep the thing going 5 years, you’re likely seeing marginal benefits.
> Unless you’re trying to keep the thing going 5 years, you’re likely seeing marginal benefits.
Not GP, but yes: that’s exactly what I’m trying to do. I think that people should generally expect 5+ years out of their devices. And in a world where user-replaceable batteries are decreasingly common, it makes increasing sense to change habits to preserve the built-in battery.
What's wrong with expecting 5 years? Am I insane to expect an electronic device to last as much as possible? And if I had to come up with s number, I'd say 10 years at least.
How do you manage that with magsafe/qi 2 chargers if you want to benefit from the greater efficiency and magnetic alignment? They’re all USB-C, and you can’t trivially buy USB-C chargers that are good for only 5W.
My phone doesn't support magnetic alignment, so I'm not really concerned with that. While I can't speak for other phones, my S24 has a setting that limits charging power to 10W, which is fine enough for me. I'd love a 5W limiter, though. The rest of the formula is a combination of Apple and Ikea. Stick to the name brand stuff, the horrors within the average 10-30W USB charger would make any electrical engineer cower in fear.
I really like Ikea's cheaper Smahagel chargers, by the way. They have very good electrical separation, they're cheap, and only run at 5W. The way they're shaped makes it easier to cram a bunch of them into a power strip, which is nice. Can't speak for the USB-C Ikea chargers though.
We have a bunch that are USB-A to micro-USB to the charger?
If you want to use the newer chargers, I’d think you’d want cooling and airflow. At some point, I want to build a MagSafe stand with a low RPM silent fan on it.
My current thinking is that the phone shouldn’t negotiate a higher wattage than it wants. Hypothetically, you could bolt it to a 1000W charger, and if it only asks for 30W, that’s all it’ll get.
The concern isn't that a 9000W charger will fry a phone expecting 30W, it's that charging at 30W subjects the phone/battery to more stress/wear than charging at 5W.
I believe current battery technology is optimized for fast charging. You are incurring damage every time your battery goes below 20% or exceeds 80% (see current EV charging recommendations).
Even LinusTechTips did a video that showed the length of charging doing more damage than fast charging. For the concern about thermal damage, most phones will throttle their charge if they become too warm.
Personally, I feel my wireless charger in the car does the most damage. It generates more heat and holds the battery in a charging state for longer
Thanks for bringing up that LinusTechsTips video - I'll try and track it down. I would not have expected that conclusion. I've already said in another comment on this thread that I'd expect the opposite!
Readit News
At my work, we have an X-ray machine for PCB reverse engineering. On Fridays we throw in random stuff from around the office, and sometimes make videos about what we find inside.
A few weeks ago we released an X-ray teardown of several other, older chargers. Very interesting to compare with these fancy new ones!
https://youtu.be/4h4qabPsPfI
Note that the audio mix for the microphone fell in the left channel only.
Apart from that, interesting images!
What a funny, positive way to point out our error.
https://youtu.be/z09X_ZnAcLs
Happy to take recommendations for other stuff to drop in there and film!
Also if this sounds cool to you, we're hiring US citizens.
https://redballoonsecurity.com/company/careers/
Curious, does this machine get past the top copper layer?
Western distributors tend to only stock western/japanese brands of these, but they can make up a sizable fraction of the BOM (especially electrolytic capacitors) so knowing who the big players are comfortable with using is very handy. LCSC stock a lot, but its nice to know which suppliers have been proven in use.
Watch out. Some of the suppliers you’ve never heard of are capable of delivering good parts to companies like Apple but still have ultra cheap parts available retail.
You can’t rely on brand names in this space.
[1] https://www.amazon.co.uk/Apple-20W-USB-C-Power-Adapter/dp/B0...
0: https://www.amazon.co.uk/UGREEN-Foldable-Charger-Support-Com...
I'm guessing an Apple 40-60W UK version might come in somewhere in between in size?
There's also the Anker Nano 45W, at 49 × 49 × 34 mm: https://www.amazon.co.uk/dp/B0DPR2VYQF
https://9to5toys.com/2018/11/09/apple-and-amazon-deal-iphone...https://www.cnet.com/tech/mobile/apple-pumps-up-its-amazon-l...
(I think there may be a few other top-tier brands who get this special treatment from Amazon.)
Just don’t buy from random listings with vendors named TREGARBLE or something. Inspect it upon arrival and send it back if it’s a problem.
I wish there was something like this for Europlug chargers. Ironically, the most compact USB adapter for me so far is one with a US plug, combined with an US-to-Europlug adapter, which can be made very compact, but seem a bit risky at 220V, given that US plugs expose the prongs while connected.
Better than that. You just move the biggest (earth) pin and the other pins fold automatically with it (in the opposite direction!), via a perfectly weighted/sprung mechanical linkage. It's a very smooth, elegant, robust action. Whoever designed it should get some design awards!
https://a.aliexpress.com/_EuPD4j8
It can deliver 50 watts entirely to 1 port, unlike most others where they mean 25 watts per port.
$5.50 with free shipping.
You couldn’t pay me enough money to plug this into a building’s electrical distribution system, it’s drawing ~3A at 120V (60W at 5V plus inefficiency) and in a very small form factor, I sure hope the engineering and QA of that $5 charger is up to par. Did they include an internal fuse or did they forego that to save $0.03? Who knows!
[0]: https://rollingsquare.com/products/supertiny-the-smallest-65...
Hot but not too hot
Many devices are made larger simply to have more surface area to spread the heat over to stay within the law.
And batteries can charge pretty fast these days. Modern pocket supercomputers keep track of battery temperature to keep things within defined limits during charging.
AFAIK the real problem, longevity-wise, for these batteries in normal use is the time spent at extremes of charge (<20% or >80%, ish).
That all said: Sure, some phones have options.
My Samsung phone does some man-behind-the-curtain tricks to attempt to make it reach 100% just before it predicts that I'll unplug it (eg, when I wake up). The idea is to maximize the charge on the phone while also keeping it at 100% SoC for as little time as practical. This probably works great for people with regular schedules (which is to say: people who are not like me).
This phone also lets me explicitly disable various fast-charge modes. I think there's at least two different modes that I can turn off (but I leave them all turned on).
And there's also a mode that limits the maximum charge to 85%, to promote long-term battery health. I have this mode engage automatically when using wireless charging, which is something I only do with the wireless charging cradle on my car's dashboard. (I do want the phone to be powered while I drive, but I don't normally need anything to work extra-hard to cram that last 15% into the battery when I'm on a long drive. It's a good balance, for me.)
Deleted Comment
USB-PD now has a standard for having sink devices request a particular current from the charger, meaning that you could actually remove a converter from the sink device side, because with a programmable source, the current limiting happens on the power supply side. Cool stuff especially for small electronics like wearables.
Generally though if you want to charge with USB-PD and accept all kinds of chargers, the sink device will have to have its own charge control PMIC.
All this negotiation happens over a side band via the "CC" pins on the USB-C connector.
My main criteria are (1) dual USB-C ports to charge multiple devices in one location, (2) compact enough to not block the other receptacle, and (3) ports face down/to the side so can fit between the wall and furniture. Unfortunately most chargers fail at least one of these.
I've recently been replacing some of the wiring in my house as part of a renovation, and I discovered that Leviton sells outlets with PD USB-C built in now! Not talking about the useless 2A USB-A "built-in" chargers of yore, now they actually have proper PD up to 60W!
They do also sell non-PD, so it requires some careful checking of the model numbers. And the 60W one is pretty large (the in-wall part) so it might not quite fit in an existing wallbox if it is a small one. But briefly: - T5636: two USB-C PD, up to 60W total / 60W individual or 30W each if both in use - T5635: two USB-C PD, up to 30W total / 30W individual or 15W each for both - T5634: one USB-C PD and one USB-A. USB-A is 10W and USB-C is up to 50W (even if both are in use) They also make T8xx versions of these that have 20A receptacles (NEMA 5-20R) but those are harder to find.
They also make other T56xx/T58xx which have non-PD USB-C, good for places like bathrooms where shavers/etc work fine on 5V.
I've found that putting a few of these around has eliminated a lot of the Anker chargers I used to have sticking out everywhere. They're completely in-wall and they leave both outlets free. If I need 100W for my computer, I'll still use a separate charger, but otherwise these are fine.
The only point they don't hit on your list is the ports facing down, but because they're flush at the wall, that means they don't interfere with furniture (any more than having any plug plugged into the outlets at all would).
If you're in Europe/elsewhere, not sure if other manufacturers make similar devices. I know Legrand makes some 30W PD ones in the US market, and as they're French, maybe they make them for others as well.
I might use these in my basement remodel since I can easily install deeper boxes. A right angle connector cable would also solve the issue of the port direction.
That being said...
I can't be the only person who consciously avoids fast-charging my phone. My whole apartment is full of wireless charging pads intentionally plugged into weak chargers (wireless charging avoids putting wear on the USB port). 60 watts can't possibly be healthy for a battery small enough to fit into a phone.
I work at a place with a huge phone fleet. We have interns study our telemetry and records because I kids like phones and they find ways to save us money. We allow for low friction replacements of phones at 12 months — the average replacement is ~27. The most common issues are cracked screens and excessive scratching on iPhone 16 and a Samsung I cannot recall. Batteries are only an issue for field devices subject to excessive cold or heat.
Unless you’re trying to keep the thing going 5 years, you’re likely seeing marginal benefits.
Not GP, but yes: that’s exactly what I’m trying to do. I think that people should generally expect 5+ years out of their devices. And in a world where user-replaceable batteries are decreasingly common, it makes increasing sense to change habits to preserve the built-in battery.
My last phone went for 6 years, and the only reason I replaced it is because one of my banking apps dropped support for Android 8.
I really like Ikea's cheaper Smahagel chargers, by the way. They have very good electrical separation, they're cheap, and only run at 5W. The way they're shaped makes it easier to cram a bunch of them into a power strip, which is nice. Can't speak for the USB-C Ikea chargers though.
If you want to use the newer chargers, I’d think you’d want cooling and airflow. At some point, I want to build a MagSafe stand with a low RPM silent fan on it.
Even LinusTechTips did a video that showed the length of charging doing more damage than fast charging. For the concern about thermal damage, most phones will throttle their charge if they become too warm.
Personally, I feel my wireless charger in the car does the most damage. It generates more heat and holds the battery in a charging state for longer
My previous phones never even got below 90% in their lifetime.
Also I am using magsafe which due to the magnet alignment leads to a high efficiency transfer at least.