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I was looking forward for Ken Shriiff-style charger reviews ([0], [1]) and was disappointed to find out this is just pictures, with almost no analysis.

FWIW, from the photos, it looks like the charger is not very bad from safety perspective -- there is a wide, healthy space between high and low side. (unless there is a diagonal trace in the "The back of the PCB" photo, between high and low voltage sides.. but it is so absurd if true, I think it is just a camera artifact)

[0] http://www.righto.com/2012/03/inside-cheap-phone-charger-and... [1] http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-ap...




> I was looking forward for Ken Shirriff-style charger reviews

Ha ha, thanks! I agree with you that it looks okay from a safety perspective. It looks like they built the charger with reasonable quality, not cutting corners, but it's not at the Apple level of (over-)engineering. The one sketchy thing is the charger panel that just pops off (instead of being glued/welded), potentially exposing the user to high voltage.

One interesting thing is the amount of complexity that USB-C adds. The charger has a separate daughter board for the Cypress USB-C controller chip. This chip contains a 32-bit Arm Cortex-M0 CPU running at 48 MHz. I believe that works out to about 8 Cray 1 supercomputers using the Dhrystone benchmark.

The switching power supply is a quasi-resonant flyback topology. To oversimplify, the incoming AC is rectified to DC, chopped up into pulses that are fed through the flyback transformer. The output from the transformer is rectified, yielding the low-voltage, high-current DC output.

One somewhat advanced feature is that the output is not rectified by a diode, but by a MOSFET controlled by the controller chip. This is called synchronous rectification. This improves efficiency because you don't have the voltage drop you get across a diode.

The SMPS controller chip is interesting. Most switching power supplies have an optoisolator to provide feedback between the output and the control chip. But this control chip connects to both the input side and output side; it contains an inductive isolator internally. The control chip also contains the MOSFET that chops up the input voltage. So the big controller chip replaces multiple components in a typical charger.

The LED indicator is a bit puzzling. There's a TL431 voltage reference chip next to it. The TL431 is extremely common in chargers to provide the feedback for voltage regulation, but apparently it's being used here to drive the LED.


You're saying that our phone chargers have the equivalent of EIGHT of the fastest computers in the world in 1976? Wow.


A usb c controller is quite complicated. The protocol is not simple at all.


It's still mind-blowing that if you wanted a USB-C controller in 1976, you'd need $64 million dollars worth of computing power.


You would need more than that, since a significant cost is already built into the economies of scale of making non-leading-edge chips.

Exponential growth is a crazy thing.


If it's doing just power charging it should be much simpler, no? Maybe there just aren't any USB-C charger-only microcontrollers out there? Or perhaps the protocol negotiation happens at such fast speed that you have no choice but to use a fairly fast microcontroller?


I guess it's important to remove the charger from the socket when you're not using it, or that computer will keep eating power.

On the other hand, would be fun if you could run complicated calculations on just your charger.


The USB chip (like many microcontrollers) has clock gating and sleep modes so it uses almost no power when idle. When running it uses 10 mA (50 mW) which is pretty low, but in deep sleep mode it uses just 100 µA (0.5 mW). In comparison, a desktop processor can use 95 W or more and the Cray 1 used over 100 kW.


Need constant current for steady LED brightness, which the TL431 can certainly do. Maybe they just wanted to use a chip they were already sourcing in large quantities.


Constant current for a single blue LED is a little nuts to me, but you’re probably right and it made financial sense somehow.


> The one sketchy thing is the charger panel that just pops off (instead of being glued/welded), potentially exposing the user to high voltage.

That sounds pretty sketchy indeed. Isn't that terribly dangerous? Could a child pop it off? Does that meet legal safety requirements for this kind of product?


"The usage of the highly integrated PI controller reduce the number of additional components required for the system"

There's a lot of clunky grammar in this post. Maybe it's a submarine advertisement?


The clunky grammar is because the site is run by Chinese people who do not have particularly great English skills.


Anker (the company whose product is profiled) is also run by Chinese people.

Which proves absolutely nothing, of course. But it is consistent with how this sort of thing might happen. Companies often hire someone from their own country to do stuff for them.

EDIT: I think people have not understood what I'm saying here. I'm not trying to imply anything bad about Anker. I'm trying to explain what the comment two levels above mine may have been implying. The fact that this site is Chinese isn't a refutation of the scenario they're suggesting, it's part of it. (On a side note, I charged my phone on an Anker charger last night.)


I thought it was started by some Xooglers. Obviously, the products are coming from China, and I imagine a lot of the design work is done there, now.

After its launch, the emphasis seemed to be a decent level of quality, i.e. it will actually be what it says on the tin. The specs we provide, it will conform to.

Which has led me to turn to Anker products in order to get a "known quality."

Has this changed?


Wikipedia suggests that it was a singular xoogler, but other than that this aligns with what I know to be true. https://en.wikipedia.org/wiki/Anker_(electronics)


I'm certainly not aware of any change. I continue to regard Anker as a reputable brand which seems to try to offer good quality products at a budget price.

I'm just playing devil's advocate here. Someone advanced a theory that it could be "submarine advertisement", another person said the explanation is just that the site is Chinese, and I said that doesn't refute the notion. I'm not trying to defend that position; I'm just trying to keep the reasoning sound once that the exploration of that hypothetical has started.


> once that the exploration

There's a lot of clunky grammar in your post. Maybe it's a submarine advertisement?

See how ridiculous it is to assume grammar errors imply nefarious ends? You're not playing devil's advocate, you're backing up a crackpot statement.


I'm not backing anybody up. If someone tries to refute a crackpot but their refutation doesn't make logical sense, then their refutation doesn't make logical sense. If I point this out, it doesn't mean I support the crackpot.

Logic and rational discourse are not a game where there are only two sides, and a statement against one is automatically a statement in support of the other.




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