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Teardown of Apple 40W dynamic power adapter with 60W max

chargerlab.com

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Re: Teardown of Apple 40W dynamic power adapter with 60W max

#221

Post by ryukoposting »

Marsymars wrote: post #39
ryukoposting wrote: post #34

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.

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.

Re: Teardown of Apple 40W dynamic power adapter with 60W max

#222

Post by ryukoposting »

Schnitz wrote: post #64
gruez wrote: post #48

Earlier quoted context omitted.

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.

What is the logic or science behind that claim? I’ve fast charged my iPhone 16 pro (heavy user) daily if not more often for a year using Apple chargers with the charge limit set to 80%. Remaining battery capacity is still 100%, which is something I’ve never had after a whole year. Fast charge doesn’t seem to hurt.

My guess is that, from the factory, Apple's firmware doesn't actually charge the battery all the way up to its 4.2V "full" threshold. It's probably stopping at 4.12 Volts, or something like that. Then, that threshold will slowly rise over the years in order to keep perceived battery life consistent. Eventually, after several hundred (or maybe a couple thousand) cycles, the threshold stops rising at around 4.2 Volts, and that's when you'll start to see the "battery health" number start to decline.

While I'm not an Apple engineer, I am an embedded systems engineer. I promise you, this kind of trickery is commonplace in consumer electronics. It's also far more common in expensive stuff (phones, laptops) than in cheap stuff (power banks, vapes). Cheap stuff could do this, it's not hard, but the people making those devices don't get paid enough to care.

Point being: A lithium ion battery's capacity is reduced every time you charge it - sometimes by only a couple mAh, but still. This is intrinsic to the chemistry. Your phone is doing things behind the scenes to mitigate that wear, but wear still happens. If you intend to keep your phone beyond its designed 2-3 year lifespan, it behooves you to keep charging current down.

Re: Teardown of Apple 40W dynamic power adapter with 60W max

#223

Post by seec »

londons_explore wrote: post #218
seec wrote: post #217

Earlier quoted context omitted.

Yep. AliExpress things, it is rarely as much of a good deal as it first appears. I have been burned many times. For things that you don't care about or don't need to rely on it's fine but there is too much fuckery going on to trust it for anything of importance. That being said, Amazon isn't much better nowadays and I have been pleasantly surprised by some items from AliExpress. However one should not expect western…

Oddly I find the reverse. They apply random coupons only at the final checkout stage and I often end up paying only half for the items I'm buying, especially if I order many items. I seem to get the 'delayed delivery' coupon every time even if the delivery is on time for example, and sometimes that coupon is worth more than the item itself for low value items.

I haven't made any purchase recently so maybe that's their way to subsidize the cost of various laws put in place in the EU recently (tax and shipping). But maybe it's also because you buy from the US?

It doesn't matter much anyway; I stopped buying there because I am a bit tired of too random quality that doesn't make the "savings" really worth it. For example, I bought a connected outlet that was half the price of ones from an EU brand but the app is pretty bad (data logging and display is terrible) and build quality worse. I also bought various RCA cable for an old amplifier and all of them were producing noise, I got a good one from Amazon (made in Germany) and no problem.

Re: Teardown of Apple 40W dynamic power adapter with 60W max

#224

Post by tecleandor »

jstrieb wrote: post #172
tecleandor wrote: post #121

Earlier quoted context omitted.

Ha! I laughed at the "my left ear enjoyed it" comment. Note that the audio mix for the microphone fell in the left channel only. Apart from that, interesting images!

I'll let the right people know, thanks to you and the YouTube commenter! What a funny, positive way to point out our error.

I guess that it was edited with the laptop speakers, instead of headphones, and that's why it wasn't noticed. No worries, it can happen!

Re: Teardown of Apple 40W dynamic power adapter with 60W max

#225

Post by tecleandor »

cenamus wrote: post #144
tecleandor wrote: post #120

Earlier quoted context omitted.

That'd be an MRI. A CT is, simplifying, an x-ray machine that takes lots of images in slices, then analyze them with certain algorithms to reconstruct 2D and 3D images of the interior of the 'subject'.

Well, not really in slices, but from all angles. So with a computer you can reconstruct the density of whatever you're imaging and also do the slices

Yeah true, I was still half asleep and couldn't explain further. It's more like you image from lots of different viewpoints, then calculate a slice, then join the slices to form a volume.

It's better explained visually (at least to me) :P

Re: Teardown of Apple 40W dynamic power adapter with 60W max

#226

Post by Reason077 »

londons_explore wrote: post #163
quickthrowman wrote: post #127

Earlier quoted context omitted.

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 ch…

OP is in the UK where every circuit has a GFCI, making it pretty much impossible to get an electrical shock due to isolation failure (in a typical year, not a single person dies from electrocution in UK homes). Fire is more of a concern, but this is indeed internally fused and the IC has both overcurrent and overheat protection - both of which are effectively 'free', so there are no cost savings to not include them.

Only relatively new (past 20 years or so) buildings in the UK are required have GFCIs (called RCCBs in the UK) on every circuit.

Older installations can be retrofitted but there is no requirement to do so.

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