Macbook charger teardown: surprising complexity inside Apple's power adapter • Hacker News Board

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#161

Post by Alupis » Wed, Nov 25, 2015, 9:31 PM UTC

Bud wrote: post #122

throwaway420 wrote: post #30

Despite the visual appeal of their products, Apple normally does a very good job with prioritizing function over form except in this case with the charger wire being so fragile and thin. I know I'm not the most careful and delicate person in the world, but the failure rate here is ridiculous compared to other similar products I own. The end of the cable gets frayed every single time. Otherwise, Apple makes ridiculous…

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

Way back in my computer repair days, I used to commonly see macbooks with horrendously frayed and/or just generally poor condition chargers. While, other laptops didn't seem to have that issue nearly as often (although breaking the DC jack was a common problem for those folks, but that's a different issue).

You shouldn't have to be tender and gentle with the power cable for your device... it should be durable and stand up to abuse. After all, it's for a laptop which may experience hard yanks as people walk away with it plugged in, the cable being stepped on or crushed by a chair, being thrown into a bag not coiled (or sometimes coiled too tightly), dropped from waist-height (or higher), thrown to a friend, etc.

It's not unreasonable to expect these things to be very durable. Functionality and durability should take precedence over design aesthetics here.

(as an aside, the white color always ended up looking filthy in short while, and was nearly impossible to restore to bright white)

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#162

Post by kens » Wed, Nov 25, 2015, 9:35 PM UTC

eropple wrote: post #157

Brakenshire wrote: post #82

Earlier quoted context omitted.

I'd gladly exchange Magsafe for generic interchangeable chargers. One charger for a laptop, tablet, smartphone and e-reader, and provided as a matter of course in cafes, libraries, trains, workplaces etc would be superb.

I under no circumstances want my probably-not-very-secure peripheral bus accessed by things provided by a matter of course in cafes, libraries, etc. Magsafe is stupid and that is fine by me. This is also why I carry my own USB adapters rather than relying on others', and have a USB condom (they call them SyncStop now, I think, but that one is big and weird) in my wallet just in case.

Magsafe actually isn't stupid - there's bidirectional communication with the laptop over the data pin in the middle of the connector, using the 1-Wire protocol. The protocol is probably simple enough to have no security issues, but now I wonder if a malicious connector could carry out an attack (buffer overflow, bad data, etc). Some security engineer might want to investigate this...

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#163

Post by amartya916 » Wed, Nov 25, 2015, 9:36 PM UTC

lxmorj wrote: post #77

cjensen wrote: post #53

Earlier quoted context omitted.

I have seven year-old chargers which work fine. Neither you nor I are unicorns: there are plenty of others for whom it breaks constantly or never breaks. I'd love to know what it is we do differently.

Wrap it and unwrap it multiple times per day. Simply having two and keeping one at the office and one at home will 4X the lifespan of your charger, since you aren't wrapping it daily. I also Sugru mine like this on both ends of the cable: http://d1u2s20mo6at4b.cloudfront.net/wp-content/uploads/appl... I'm considering making a mold so the Sugru looks nice when done and selling robustified chargers on Shopify. I alread…

I've done the same for my chargers as well (as in using Sugru). I love your idea of making a mold for better finish as well as selling the "robustified" chargers. I think there will be a market for this, but best of all, I think you can pull this off on demand too (in a way?). I also think the $99 charge is fair.

A quick back of the envelope calculation is as follows:

$80 for 85 watt charger on amazon [0] + $3 * 2 for Sugru on both ends of the cable [1] + $5.95 for USPS priority 3 day shipping [2] ~= $92

With this supply chain (if it can be called that), you can still estimate shipping the charger to the end consumer within 6 days (2 days with Prime shipping with Amazon + 3 days for USPS). I did not factor in the Prime membership and the mold in the costs though, but it can be factored in fairly easily. Also, I chose to use USPS shipping costs, naturally your mileage will vary because your company/business probably has higher costs (cool service by the way, and congrats :))

[0] 85 W charger: http://amzn.com/B004L6MLPQ [1] Sugru 8 pack: http://amzn.com/B00EU7DBNM [2] Small flat rate box from USPS: http://pe.usps.com/text/dmm300/Notice123.htm#2517977

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#164

Post by pmelendez » Wed, Nov 25, 2015, 9:39 PM UTC

throwaway420 wrote: post #30

Despite the visual appeal of their products, Apple normally does a very good job with prioritizing function over form except in this case with the charger wire being so fragile and thin. I know I'm not the most careful and delicate person in the world, but the failure rate here is ridiculous compared to other similar products I own. The end of the cable gets frayed every single time. Otherwise, Apple makes ridiculous…

> Otherwise, Apple makes ridiculously durable products

Except for the first USB cables for iPhone5, those things only last a few months. First time I have had to buy three cables for charging one device within a year.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#165

Post by d_v » Wed, Nov 25, 2015, 9:42 PM UTC

pmelendez wrote: post #164

throwaway420 wrote: post #30

Despite the visual appeal of their products, Apple normally does a very good job with prioritizing function over form except in this case with the charger wire being so fragile and thin. I know I'm not the most careful and delicate person in the world, but the failure rate here is ridiculous compared to other similar products I own. The end of the cable gets frayed every single time. Otherwise, Apple makes ridiculous…

> Otherwise, Apple makes ridiculously durable products Except for the first USB cables for iPhone5, those things only last a few months. First time I have had to buy three cables for charging one device within a year.

Did you know those are covered under your iPhone warranty? As long as you have a warranty (including AppleCare, so up to 2 years), they will replace the USB cable and headphones for free.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#166

Post by mc32 » Wed, Nov 25, 2015, 9:43 PM UTC

Bud wrote: post #122

throwaway420 wrote: post #30

Despite the visual appeal of their products, Apple normally does a very good job with prioritizing function over form except in this case with the charger wire being so fragile and thin. I know I'm not the most careful and delicate person in the world, but the failure rate here is ridiculous compared to other similar products I own. The end of the cable gets frayed every single time. Otherwise, Apple makes ridiculous…

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

Of course people are "too rough" with their power adapters, but the mfg should take that into account when designing such a component.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#167

Post by Alupis » Wed, Nov 25, 2015, 9:43 PM UTC

weland wrote: post #18

This is a pretty interesting article! I raised more than my fair share of eyebrows by telling people I'm not really surprised with this kind of complexity (note: I'm an EE by formation, I took a frickin' two-semester course on power supplies) but that it doesn't fully justify the price difference. Also, Jobs was a blatant liar :-). The SMPS in any modern computer is based on a standard topology that Rod Holt -- thoug…

It's interesting that most of the author's claims about quality (and reasoning to not buy a non-Apple brand power supply) boils down to "look at all the extra stuff on the circuit board in the apple power supply". Surely not everything Apple put in the charger was absolutely required, and that also doesn't mean someone else couldn't deliver the same quality with less components.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#168

Post by specialp » Wed, Nov 25, 2015, 9:45 PM UTC

All Apple needs to do to stop their cables from fraying at very high rates is to use a continuous flex cable like these: http://www.igus.com/wpck/15029/productoverview_CF?C=US&L=en I used to work on amusement rides, and we had a problem with cables on bumper cars breaking very often due to movement. After replacing them with these they never failed again.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#169

Post by Bud » Wed, Nov 25, 2015, 9:45 PM UTC

Alupis wrote: post #161

Bud wrote: post #122

Earlier quoted context omitted.

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

Way back in my computer repair days, I used to commonly see macbooks with horrendously frayed and/or just generally poor condition chargers. While, other laptops didn't seem to have that issue nearly as often (although breaking the DC jack was a common problem for those folks, but that's a different issue). You shouldn't have to be tender and gentle with the power cable for your device... it should be durable and sta…

Great, so you explain how Apple's design is faulty, and how it could be improved. I think you'll find this is easier blustered about than done.

PC chargers, for instance, are universally worse. A lot worse.

This design already does the best job in the industry at handling hard yanks——that's what MagSafe is for. And it does fine with ordinary, expected use and abuse of the cable. And it does great with being thrown into a bag or dropped.

What it doesn't do, because that's impossible, is to magically become able to be yanked on 500 times and coiled as tightly as possible around itself, without ever wearing out. But I've offered a solution to that.

Your implied accusation that "design aesthetics" have taken precedence over functionality and durability is unfounded. The fact is that Apple's charger works a lot better and is a lot more durable than the competition.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#170

Post by Bud » Wed, Nov 25, 2015, 9:46 PM UTC

mc32 wrote: post #166

Bud wrote: post #122

Earlier quoted context omitted.

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

Of course people are "too rough" with their power adapters, but the mfg should take that into account when designing such a component.

Yep. And Apple did. That's why there is more robust strain relief than it used to have, and that's why there is MagSafe, which is vastly superior to the PC side when dealing with yanks and ordinary abuse.