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Search - "usb charger"
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My friend called me up once saying the new mouse he bought to use with his laptop wasn't working.
I told him to just plug it into the usb port and it should just work immediately.
After an hour of trying shitload of things I finally gave up and said I'll come over and have a look.
And there was his mouse.
Connected to a phone charger.
To a wall outlet.14 -
6pm - arrive home from work, log into my computer and start working on side projects.
4am - Finally go to sleep after staying up all night setting up arch in a vm.
7am - Start drive to work in the snow and ice.
7:20am - car runs out of wiper fluid.
7:30am - round corner so that I’m driving towards the sun, windshield is covered in mud and I have 2% visibility.
7:35am - take off ramp towards gas station so I can buy fluid and wash window.
7:36am - Car mysteriously parked in center of off ramp, nearly smash it but have a narrow miss.
7:40am - can’t find the freaking pully in new car to pop hood
7:41am - found it.
7:50am - drove the back way to work because it cuts out traffic, but includes many steep hills that I forgot existed, come to a skid at bottom of one and am pushed out into the main road, luckily nobody is coming and I’m able to continue on my merry way.
8:01am - sit down in desk, lead staff person comes over evoking Lumbergh from Office Space and lets me know I need to be on time to work and that the snow doesn’t give me an excuse. I agree and smile and suck up and he leaves.
8:02am - pull out phone to write down notes about personal project that I thought of on drive here, phone dies. I forgot to plug it in last night.
8:04am - found power bank charger thing in desk but it uses a micro-b type usb and I only have usb type c on me.
8:10am - borrow usb from old headset in office surplus.
8:11am - writing notes. Have sudden realization that I didn’t shut down my vm and that when my computer went to sleep and subsequently locked it probably halted virtualbox and everything would be lost for the second time.
8:12am - got on devRant.4 -
Long rant ahead. Should take about 2-3 minutes to read. So feel free to refill your cup of coffee and take a seat :)
It turns out that the battery in my new Nexus 6P is almost dead. Well not that I didn't expect that, the seller even explicitly put that in the product page. But it got me thinking.. why? Lithium batteries are often good for some 10k charges, meaning that they could last almost 30 years when charged every day! They'd outlive an entire generation of people!
Then I took a look at the USB-C wall charger that Huawei delivered with this thing. A 5V 3A brick. When I saw that, I immediately realized.. aah, that's why this battery crapped out after a mere 2 years.
See, while batteries are often advertised as capable of several amps (like 7A with my LiitoKala 18650 batteries that I often use in projects), that's only the current that they can safely take or deliver without blowing up. The manufacturer doesn't make this current rating with longevity in mind. It's the absolute maximum in current that a given battery can safely handle.
The longevity on the other hand directly depends on the demand that's placed on the battery. 500mA which is standard USB 2.0 rating or 1A which is standard USB 3.0 rating, no sweat. The battery will live for at least a decade of daily charges and discharges like that no problem.
But when you start shoving 3A continuous into a battery, that's when it will suffer. Imagine that your current workload is 500mA and suddenly you get shoved 6 times that work upon you. How long would you last?
Oh and not only the current is a problem, I suspect that it also overvolts the battery to maintain a constant current all the way till the end. When I charged my lithium cells with my lab bench power supply, the battery would only take a few milliamps when it got close to the supply voltage. Quick bit of knowledge: lithium cells are charged at constant current first, then when the current drops below that, it continues at constant voltage - usually 4.2 or 4.35V depending on the battery. So you'd set your lab bench power supply at 4.2V 500mA. But in that constant voltage mode, as the battery's voltage and the supply's voltage equalize, the current drops because the voltage difference becomes lower. Remember, voltage is what causes current to flow. Overvolting at the supply to stay in constant current mode all the way till the end speeds this process up but can be dangerous and requires constant monitoring of the battery voltage.
So, why does Huawei and a bunch of other manufacturers make these 3A power chargers? Well first it's because consumer demands ever more, regardless of the fact that they can just charge at 500mA for the night (8h of sleep) and charge a 4000mAh battery from 0 to 100% no problem. Secondly it's because sometimes you need that little bit of extra juice fast, like when you forgot to plug the damn thing in and you've got only 30 minutes in the morning to pour some charge into it.
But people use those damn fucking things even when they go to bed, making that 3A torture a fucking standard process!! And then they complain that their batteries go to shit?!
Hopefully this now made you realize that the fast charger shouldn't be used as a regular charger ^^29 -
iPhones are ridiculously picky when it comes to finding a mate- um charger. And knowing why doesn't really make it any easier to understand why. If anything it baffles me more.
So, let's start with appliances that are not phones. Think Bluetooth headsets, keyboards, earbuds, whatever. Those are simple devices. They see 5V on the VCC line and 0V on ground, and they will charge at whatever current they are meant to. Usually it will not exceed 200mA, and the USB 2.0 spec allows for up to 500mA from any USB outlet. So that's perfectly reasonable to be done without any fuss whatsoever.
Phones on the other hand are smarter.. some might say too smart for their own good. In this case I will only cover Android phones, because while they are smarter than they perhaps should be, they are still reasonable.
So if you connect an Android phone to the same 5V VCC and 0V ground, while leaving the data lines floating, the phone will charge at 500mA. This is exactly to be within USB 2.0 spec, as mentioned earlier. Without the data lines, the phone has no way to tell whether it *can* pull more, without *actually* trying to pull more (potentially frying a charger that's not rated for it). Now in an Android phone you can tell it to pull more, in a fairly straightforward way. You just short the data lines together, and the phone will recognize this as a simple charger that it can pull 1A from. Note that shorting data lines is not a bad thing, we do it all the time. It is just another term for making a connection between 2 points. Android does this right. Also note that shorted data lines cannot be used to send data. They are inherently pulled to the same voltage level, probably 0V but not sure.
And then the iPhones come in, Thinking Different. The iPhones require you to pull the data lines to some very specific voltage levels. And of course it's terribly documented because iSheep just trying to use their Apple original white nugget charger overseas and shit like that. I do not know which voltage levels they are (please let me know!), but it is certainly not a regular short. Now you connect the iPhone to, say, a laptop or something to charge. An Android phone would just charge while keeping data transmission disabled (because they can be left floating or shorted). This is for security reasons mostly, preventing e.g. a malicious computer from messing with it. An iPhone needs to be unlocked to just charge the damn thing. I'm fairly sure that that's because the data lines need to be pulled up, which could in theory enable a malicious computer to still get some information in or out of it. USB data transmission works at at least 200mV difference between the data lines. It could be more than that. So you need to unlock it.
Apple, how about you just short your goddamn data lines too like everyone else? And while you're at it, get rid of this Lightning connector. I get it, micro USB was too hard for your users. I guess they are blind pigs after all. But USB-C solved all of that and more. The only difference I can think of is that the Lightning connector can be a single board with pads on either side on the connector, while in USB-C that could be at the socket end (socket being less common to be replaced). And at the end of the day, that really doesn't matter with all the other things that will break first.
Think Different. Think Retarded. Such tiny batteries and you can't even fucking charge them properly.6 -
Ha ha! Fuck you Apple. Forced to use USB c after your stupid charger games every iphone release.
Its about time. You pricks keep forcing new chargers on me. I have a drawer full of obsolete chargers.18 -
The default USB voltage hould have been specified to 6 instead of 5 volts.
Six (6) volts would allow for longer cables than five (5) volts do, since the spare voltage compensates for the resistance of cables. This is even more crucial for USB hubs. USB hubs are highly dependable upon these days due to laptop vendors dropping the number of USB ports down to two or even one. I am looking at you, Medion.
If several devices are connected to a USB hub, the voltage can quickly drop below 4.5 volts due to the resistance between the USB hub ports and the computer's USB port, causing some devices to restart themselves even if the computer's USB port is not over capacity. If it were over capacity, it would just regulate down its output voltage to prevent overcurrent.
Lithium-ion batteries need at least 4.3 volts arriving at the battery terminals to fully charge, and mobile devices are typically not equipped with a boost converter. Even if they were, they are rather inefficient, meaning they would produce significant heat and waste a power bank's energy. Other USB devices such as flash drives and peripherals might power off below 4.5 volts. However, 6 volts have solid 1.7 volts of margin to 4.3 volts, more than twice the margin of 0.7 volts that 5 volts have. On the way from the power supply to the end device, the voltage has to pass several barriers which weaken it, including the cable, connector endings, and the end device's internals such as the charging controller.
Sure, there are quick charging standards such as by Qualcomm and MediaTek which support elevating voltages to nine (9), twelve (12), and even twenty (20) volts. However, they require support by both the charger and mobile device. If six (6) volts were the default USB voltage, all devices would have been designed to accept this voltage, and longer cables could have been used anywhere. Obviously, all USB devices should be able to run on five volts as well.
Six volts would have been more stable, flexible, and reliable.14 -
Back when every mobile company had a different charger it made sense to say Nokia charger or Sony Ericsson charger.
But ever since micro usb became standard, I cringe when I ask for a micro usb charger and idiots say they have a Samsung charger not a Motorola one.
Seriously? How much do you have to think to realize if a charger works for many brands of phones it can't be a Samsung charger?7 -
One morning I accidentally pulled the charger out of my phone. It's not turned, just pulled out. I tried to plug it back, but the first attempt failed. I turned around the cable and plugged in. WTF USB?! How is this working?1
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How to charge a Drone battery with a power bank (or how to burn a battery, lipo module and maby power bank)2
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Bought me a nice phone charger for just 300€ (350$ USD).
Oh, and it brought a nice usb-c cable too. So happy 😣10 -
What is the difference between battery and rated capacity. I tried googling and theres a very technically paper with the definitions...
But what does it mean in terms of using it to charge my phone.
#Aliexpress US $6.15 72%OFF | Essager 10000mAh Power Bank Slim USB 10000 mAh Powerbank Portable External Battery Charger Pack For Xiaomi Mi 3 iPhone PoverBank
https://a.aliexpress.com/_sZXhqk8 -
So I deleted my last post looking for the next tech sale date as wanted a wireless charger because I found a deal...
It was like 60% off... But after I got buy instead regret...
The sites reviews are crap, it's a reseller apparently and no actual brand is listed...
And then I realized what I really wanted was a fast USB charger that takes a regular USB input instead of Google's choice of a microusb one ....
Another $20 down the drain... It seems the return policy is crap or non-existent... -
I've been having blackouts a lot recently which kills my desktop so thinking I should buy a UPS specifically APC UPS Battery Backup & Surge Protector with USB Charger, 600VA, APC Back-UPS (BE600M1) https://amazon.com/dp/B01FWAZEIU/...
But not sure how I would maintain it/use it.
Basically it would replace the current per strip I'm using for PC and monitor?
I don't know though how long it would last for my gaming PC though. What is the 625? I need it to last at least 5 minutes so it can shutdown properly but it's a gaming desktop... So will it be enough. I don't know what the VA means... Also I have a 4K 27in monitor...
That and I'm a bit worried this thing blows up and starts a fire...16 -
Has anyone else found that not all USB C inputs are the same? You can't just buy an cable and expect it to plug into any socket.
1. I replaced the cable for a power pack, but the new one didn't fit my OP6 socket well, no clicking and have to push it in very hard to get it to charge, and still eat to fall out
2. The pixel 2 cable fits it nicely and all cables are ready to plugin and work
3. I tried charging my new Pixel 4a with ur though but very hard to plug in. Had to install the charger and cable that came with.
4. Amazon Fire takes all of them nicely and send all the others can use the cable that came with it too8 -
!dev; New Yorkers @dfox @trogus
I'm planning to go up the One World Observatory tmr morning but not sure which ticket to buy, particularly the IPAD option with streaming video. It says you can watch them later although it also expires apparently. So I'm wondering it worth it... (I'm also thinking since it's streaming and I can share it with anyone, it means I can probably download it too... the techie way).
Also can I bring a USB charger? My plan is to sorta just sit up there in the morning. Then head to Timeout Market for lunch-dinner.3 -
Fuck Google for only including a USB C to USB C cable with the Pixel 6...
...along a USB to USB C adapter
And then have to pay $25 for basically a.... Pixel 4a 5g charger.10 -
I don’t know what my sister did but she trigged the firmware update mode by trying to charge her nexus 5x with my MacBook (USB C) wall charger.
I had to force restart the phone because it was in endless loop. Now everything is fine.