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Apple didn't revolutionize power supplies; new transistors did (2012)

208 points| Rondom | 4 years ago |righto.com

158 comments

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WalterBright|4 years ago

I didn't realize it, but my '72 Dodge has a switching power supply to convert the 12 volt system voltage to 5V for the dashboard instruments.

It's a very simple device, relying on current heating a wire to bend it to and from a contact, but it's an engineering marvel of low cost effectiveness.

But it doesn't produce "clean" 5V, there's a jitter to it. Some electronics guys have replaced it with modern circuitry (an op-amp I think) but it turned out there was a problem with clean 5V. The jitter would unstick the the analog dials, so they'd display accurately. The clean 5V didn't do that. So, they had to add more circuitry to add jitter in the supply voltage.

tim333|4 years ago

And now power supplies are getting another step smaller and more efficient by switching from silicon transistors to GaN. (https://www.cui.com/blog/how-gallium-nitride-gan-enables-sma...)

alexose|4 years ago

I've been using a GaN-based power supply for my MacBook Pro and it's just as good as advertised. Slightly bigger than a deck of cards, yet it runs cooler than the stock unit.

Hopefully this tech finds its way into more devices as it gets cheaper. It would be neat to have GaN based inverters for electric cars.

dehrmann|4 years ago

Any advice on buying these? A lot of the GaN bricks look impressive, but they're always made by a sketchy peripheral maker.

londons_explore|4 years ago

It surprises me that GaN marketed power supplies cost extra. The actual GaN transistors are under 10 cents now, and by using one you can use a smaller inductor, smaller capacitor and smaller heatsinks. Those smaller components lead to a smaller plastic case and smaller circuit board.

All of those smaller things cost less, so the finished product has lower production costs.

vwoolf|4 years ago

At first glance I thought the article would discuss GaN. Agree with the overall point; Anker seems to be making well-thought-out GaN chargers.

byw|4 years ago

Can this also be used for electric car inverters?

EastOfTruth|4 years ago

I never heard that Apple invented switching power supplies... how common is that train of thought? I've been using them since way before this article was written

FPGAhacker|4 years ago

The article is neither making or debunking that claim. It is debunking the claim that apple revolutionized computer power supplies by borrowing the switching power supply design used in oscilloscopes. It’s the second sentence of the post.

JKCalhoun|4 years ago

For its personal computer contemporaries, the TRS-80, the Commmodore PET, the Apple II's use of a switching power supply was unique. I had never heard that they invented the switching power supply.

Apple's price premium meant they often could introduce the next cutting edge technology that would soon become ubiquitous when the prices came down.

karlkloss|4 years ago

In fact, switching power supplies were used long before the transistor, they were using mechanical switches.

Car radios used mechanical switches to generate the anode voltage for the tubes, and in trains there were voltage converters using a rotating stream of liquid mercury.

musicale|4 years ago

Whenever Apple is discussed, there often seems to be a conflation of invention (coming up with something new) with innovation (applying an invention in a way that changes things.)

Apple didn't invent the personal computer, or the GUI, or Wi-Fi, or MP3 players, or smartphones, or app stores, or tablets, or smartwatches, or ARM processors – but they introduced innovative, and indeed transformative, products in those categories.

anaganisk|4 years ago

But Android did it first /s.

JKCalhoun|4 years ago

Interesting deep dive on switching power supplies. I didn't see the need to frame it by attacking Apple.

retrac|4 years ago

At the time, "Apple invented the switching power supply" was a notion going around in bad tech/sci reporting circles, so it deserved dismantling along with the power supplies.

echelon|4 years ago

> I didn't see the need to frame it by attacking Apple.

Other posters have already pointed out that this article seeks to clarify the history around Steve Jobs' (not entirely accurate) claims.

I want to focus on the fact that people find a need to protect Apple.

Apple is a 2T+ market cap corporation. It is not a friend, it is not a family member, and it is certainly not beyond reproach. It doesn't care about you -- it just wants you to spend more money on its products and services.

Don't feel bad for Apple when people call it out for bad behavior or historical inaccuracies. People should do this.

While there are people that work at Apple that legitimately care about making good products, in the macro the predominant factor is still money. It drives the whole enterprise. The very shape of Apple's solutions and good will are fit by an optimization function to obtain money.

Brand, supply chain, innovation, fierce competition, fostering loyalty, building a moat. These are the things Apple does. It's a machine that makes money selling products.

You might like Tim Cook, Steve Jobs, or many of the other product people and engineers there. That's fine. But don't form a fond bond with the company. And also realize the motivations of the leadership. They're humans -- they can do good, but they can also make mistakes and tell lies to serve their own needs.

If Apple makes products you like and enjoy, buy them, appreciate them, and leave it at that. Don't let Apple create a sense of nostalgia, closeness, or loyalty. This is artificial. The company doesn't care about you at all. It can't.

kens|4 years ago

The motivation for the article was to investigate Steve Jobs' claim, so it would be strange to remove that.

TedDoesntTalk|4 years ago

The article is debunking this claim by Steve Jobs:

"That switching power supply was as revolutionary as the Apple II logic board was," Jobs later said. "Rod doesn't get a lot of credit for this in the history books but he should. Every computer now uses switching power supplies, and they all rip off Rod Holt's design."’

fortran77|4 years ago

It's only right to clear up a falsehood promoted by Steve Jobs himself. He's not above scrutiny.

Hello71|4 years ago

the first sentence of the article:

> The new biography Steve Jobs

it was a response to the new biography.

throwawaylinux|4 years ago

Pushing false or unsubstantiated information is the attack. Investigating it and presenting facts and counter points is defense.

djmips|4 years ago

Totally agree, that aspect made me roll my eyes. Very unnecessary even if it provides a skeleton for the narrative.

amelius|4 years ago

Another article in IEEE Spectrum:

https://spectrum.ieee.org/a-half-century-ago-better-transist...

> A half century ago, better transistors and switching regulators revolutionized the design of computer power supplies

> Apple, for one, benefited, though it didn’t spark this revolution, as Steve Jobs claimed

kens|4 years ago

That's the same blog post, rewritten for IEEE Spectrum.

alan-kay|4 years ago

This is an old original post, but it still worries me.

Consider: https://en.wikipedia.org/wiki/Switched-mode_power_supply

To find this requires a combination of a few keystrokes and button pushes plus an "outlook" (rather than "inlook") attitude.

Instead, as with so many discussions in a so-called "CS" community, we find something like adolescents trying to BS each other by presenting their mere opinions as facts.

Come on! Please!

Long ago my research community put in a lot of work to make it easy to deal with many simple questions, but we didn't reckon with the sheer inwardness of so many end-users. A similar problem is that most people in CS have no idea what Doug Engelbart really did, yet just typing his name into Google will provide great info in just the first few hits.

How can the current community repair itself and start trying to become a real field again?

foxhill|4 years ago

it is the paradox of the information era: society has never had such easy and immediate access to the limits of human knowledge, and at the same time, society can’t agree on whether the earth is spherical, vaccines work, or if demonstrably corrupt politicians are really that bad.

hedgehog|4 years ago

I know someone who was an exec at Astec in the 90s and Apple was notable for being willing to pay a premium for their power supplies (I think for better efficiency and miniaturization).

ForOldHack|4 years ago

Then... how did they wind up with such utter garbage? The Astec in the Mac IIcx/ci was prone to failures. The power supply in the mirror door Mac.

esturk|4 years ago

Does anyone know of a hack or instructions that can convert a magsafe charger for old macbooks into a USB-C charger for new macbooks?

wtallis|4 years ago

I doubt that the old MagSafe chargers are capable of outputting the variety of voltages necessary to be usefully compliant with USB-C charging. IIRC, the old MagSafe chargers put a fairly small voltage on their output pins, and when a load was detected they turned on the full voltage and power—but there was no real data communication between the computer and the brick (just between the computer and the connector at the end of the charging cable). USB-PD however is a complicated protocol.

intsunny|4 years ago

There are "magsafe to usb c" dongles on Amazon and other retailers.

The run a little hot, but seem to work pretty well.

ladyattis|4 years ago

If only they'd invest more work into CMC and LC filters for such power supplies in wall warts. As someone who listens to shortwave and AM radio DX it's sometimes impossible to pick up even strong stations due to the swampy noise of SMPS devices.

nahuel0x|4 years ago

well, in some sense Apple didn't invent personal computing, MOS 6502 did.

kens|4 years ago

I'm not looking to argue over the meaning of "invent" or "personal computing", but I'll point out that Alan Kay wrote a 1972 paper "A Personal Computer for Children of All Ages" that pretty much describes the modern laptop or tablet. (He even mentions ad blockers!) Xerox PARC went on to implement a lot of this in the Xerox Alto.

It's worth taking a look at the paper to see how many "modern" ideas were described in 1972: http://www.vpri.org/pdf/hc_pers_comp_for_children.pdf

Underphil|4 years ago

It's the old classic of 'invented' vs 'popularised' at play. Both equally important I think.

ForOldHack|4 years ago

Apple did revolutionize power supplies, but not in the way that is claimed: They made it a marketing stratjey to ship utter garbage, like the Appple III, and the "Hindenbook" along with the most inexpensive, cost cutting, garbage known in the industry, until Dell and eMachines decided to use the same model:

Just look up "Apple PowerSupply Recall" and you will see they are just repeating their cost saving success/failure.

FpUser|4 years ago

Same story as with hard drive based audio players. I've been using one (if I remember correctly) from Creative long before iPod materialized. All was quiet but suddenly as iPod came it was of course called revolution.

moftz|4 years ago

Apple invented one people actually wanted to buy

pdamoc|4 years ago

> "No wireless. Less space than a nomad. Lame." - CmdrTaco

Apple is very good at maximizing "consumer satisfaction". This means giving consumer the best deal for their money considering as many of the consumer needs as feasible. Other brands ignore a lot of these needs and then they wonder why people don't buy their products when, on some details, they are much better than Apple at a lower price.

socialdemocrat|4 years ago

Seriously, those MP3 players were nothing like the iPod. This is a bit like people going on about smart phones before iPhone. I had a couple of those and the iPhone was just so far ahead, that we are not really talking about the same category of products.

A product isn’t merely checking some boxes. Checking the “has hard drive” box doesn’t make any it an iPod.

wyager|4 years ago

While obviously Jobs’ claim was false, I will say that Apple is the only company I am aware of that manufacturers power supplies which are reliably completely free of perceptible inductor whine. I have very acute high-frequency hearing and I often have to replace non-Apple USB(-C) switching power supplies with Apple ones so I don’t go crazy from the whining. Teardowns of Apple PSUs typically reveal very favorable electronic and industrial design as well.

Syonyk|4 years ago

> I have very acute high-frequency hearing...

Doesn't take "acute," just takes "not destroyed."

I've, at various points in my career, grumbled about various things whining audibly (one particular motion light sensor was defective and right outside my office for a while). The trick to getting other people to believe you ("I can't hear anything... are you sure?") is to wait for a bring-your-kids-to-work day. And ask if they can hear it.

Or, perhaps, if it's bad enough, you don't even have to do that, because the kids will ask what that horrid whining noise is. We did eventually get it fixed after that, but I was quite literally the only one in the hall who could hear it.

On the topic of power supplies, though - Apple has done some impressive work in their small power supplies. The Chinesium clones are similarly sized, they just skip literally every safety feature intended to keep mains voltage out of your USB cord...

bayindirh|4 years ago

My old MacBook Pro's power brick has perceptible inductor whine. It's not screamingly high, but I can hear it when it's near.

Probably my ears' sensitivity, and that little thing's age (~13 years) are both contributing factors.

krrrh|4 years ago

It’s extremely frustrating, and I was always surprised when I returned mid-range USB chargers because of whine only to receive a replacement with the same problem and hundreds of reviews that failed to mention it. I’ve never had an issue with Apple chargers, and the extra cost is money we’ll spent.

Buy genuine Apple chargers, if not for you, then for your dog.

fsckboy|4 years ago

> Apple is the only company I am aware of that manufacturers power supplies which are reliably completely free of perceptible inductor whine...I often have to replace non-Apple USB(-C) switching power supplies

it's a well-studied economic fact that monopolists generally sell higher quality products, and it helps them maintain their monopoly. With their market power and the fat margins they earn, there is plenty of budget to do R&D and have achieve scale benefits. Their optimum-profit product-mix and pricepoints are skewed higher. Nobody complained about IBM mainframe quality, nor Bell Telephone quality.

So, it's not testimony to Apple's prowess, it's simply a cookbook outgrowth of their product differentiation strategy.

krono|4 years ago

This is so off-topic, but no one ever believes me when I'm complaining about a wall adapter across the room driving me mad. Glad to know I'm really not imagining things hah!

errantspark|4 years ago

Don't worry, that problem will solve itself with time. Just let the lowpass in your ears grow a bit. ;)

I will say I have been very impressed with Anker's GaN power bricks of late.

kcb|4 years ago

My Macbook Power Supply whines like crazy, especially when under load. The one thing that drives me crazy that I rarely see talked about is PWM fan control. I think different manufactures use different frequencies but it's usually far more annoying than the motor/air movement noise.

vmception|4 years ago

I'm guessing this article is from 2011, back when Apple fans were just ending their role as being a niche that believed anything.

At this point it is - I think - a pretty common assumption that Apple just puts things together in a decent ecosystem. If Apple devices offers a new frequency range, its because Qualcomm's radio allowed for it, which was dependent on other things further in the stream.

This is an interesting trip down memory lane. Apple still says magical sometimes in their keynotes, but nobody is really mystified only occasionally glad they decided to offer something in that way, since its more about the Apple implementation than the Apple innovation.

gumby|4 years ago

Not an Apple fanboy but I don’t this is completely correct. As a huge buyer of semiconductors they can, when they want to, exert a lot of pressure on suppliers. Famously they did this with Gorilla glass; they have done so with Intel and qcomm. Sometimes not so successfully (all the expense on the “liquid metal” company, for example).

It’s not all sheer pressure; they do a lot of collaborative design. After all they have one of the best semiconductor design teams (both digital and analog) around. And they are on standards bodies; they allegedly (some non-Apple people told me) contributed contributed significantly to USB-C.

I emphasized completely because in the modern ecosystem it’s broadly true (RAM, displays etc)

_carbyau_|4 years ago

I don't like Apple generally. And it wasn't "their" technology - but thank fuck they brought "better than 1080p" screens to the mainstream.

Throughout the 90's screen resolutions were getting better and better. Then LCDs came and 1080p stopped mainstream screen resolution improvements for at least 5 years.

Thankfully Apple got the screen resolution race going again.

userbinator|4 years ago

No need to guess, the year is in the URL.