Wednesday, December 31, 2014

The Memory Leak Bug Of Lollipop -Android 5.0.1

Android Lollipop – the much anticipated update to Google's OS that brought about that modernistic visual overhaul everyone seems to be craving – the Material Design. But of course, Android 5.0 is more than pretty visuals – there is lots going on under the hood, looking to provide a more stable, smooth, and powerful performance.



Of course, such big new releases are not without faults and no company is safe from launching a dud. As you probably remember, iOS 8.0 caused a lot of headaches for users and Apple alike(especially the 8.0.1 update) , so did iOS 8.1, which was released as soon as the new iPad Airs were announced. This prompted for updates to be released in rapid succession, with some ironing still left to be done.
0.1 updatehas been reported to have a nasty memory leak, which tends to take up 1.3+ GB of RAM, resulting in on-screen apps constantly being force closed and the used phone auto-returning to home screen often. A thread on the Android Issue Tracker forum has been opened and users have reported various Nexus devices to be afflicted , so it appears no one is safe.


Well, Google's Android is also angering early adopters, as the hot-out-of-the-oven      5.
The good news is that the cause of the memory leak may have been pinpointed and the thread has been closed and marked as “FutureRelease”, which means that the fix will be added to an incoming update (which update, and when, is unknown, but we'd imagine – as soon as Android devs can arrange for it to happen).

Android 5.0.1 memory leak discovered, fix under works

The Internet Explorer And Windows 10

Microsoft will launch Windows 10 next year, probably in late summer / early fall. The new iteration of the OS will work on many devices, from smartphones to tablets and PCs, representing a big step forward compared to Windows 8.1 and Windows Phone 8.1- that’s why Microsoft decided to name it Windows 10, eluding the Windows 9 moniker altogether. 
According to ZDNet, one of the major changes that Windows 10 will bring is a brand new browser. 
Currently codenamed Spartan, the browser will still rely on Microsoft's Chakra JavaScript engine and the Trident rendering engine (used by Internet Explorer 11). Even so, ZDNet’s sources have it that this is definitely not Internet Explorer 12, but a new and “lightweight” browser that will be available on desktop computers, tablets, and smartphones. Spartan could resemble Chrome and Firefox more than Internet Explorer as we know it.
Despite the arrival of the new browser, it’s said that Internet Explorer will still ship with Windows 10 (backward compatibility reasons being quoted), so this is not yet the death of IE - though we assume that it is the beginning of the end.
Microsoft will reveal new details about Windows 10 in January (next month), so maybe we’re going to find out more about Spartan then. 
P.S: The image above presents a well-known, humorous take on the fact that Internet 

Windows 10 might be the beginning of the end for Internet Explorer

Tuesday, December 30, 2014


Convalescent plasma therapy (CPT)

This is not new but old techniques, but seriously discussing and researching now a day. A couple of days back NPG reported about the ongoing clinical research in CPT. The CPT, earlier really helped to reduce the fatality of N1H1 victims. Now the same approach is trying with EBOLA victims. 


Clinical trials of convalescent plasma therapy (CPT) have started in the past few weeks in Liberia, and are due to begin soon in Guinea and Sierra Leone. If the therapy saves lives, the approach could quickly be scaled up. 

Success would also raise awareness of CPT’s potential to treat other new and emerging infectious diseases for which there are no readily available effective drugs or vaccines, such as SARS, avian influenza and Middle East respiratory syndrome (MERS). “Clinical trials of convalescent plasma should be considered in other emerging infections,” says David Heymann, an infectious-disease researcher at the London School of Hygiene and Tropical Medicine, and chair of Public Health England. 

What is Convalescent plasma therapy (CPT) ?


Basically this is a plasma transfusion treatment. The plasma will be collected from patients who recovered from the infection. Only plasma with a high neutralizing antibody will e used. The treatment involved an infusion of 500 mL of plasma over a four-hour period on day two of the stay in the intensive care unit. To the extent possible, the treatment and control groups were matched by age, sex, comorbidities, and disease severity at ICU admission. 

Nonetheless, patients in the treatment group had more risk factors for severe disease, including a lower lymphocyte count, greater prevalence of obesity, and presentation with more severe symptoms. 

Convalescent plasma therapy, which is safer now than in the early half of the 20th century because of donor screening, virological and microbiological testing, and apheresis, may have some advantages over antivirals.

Collecting convalescent plasma presents some feasibility issues during the course of an epidemic because the plasma will not be available at the beginning of the outbreak.

Convalescent plasma therapy (CPT) Gaining Momentum

Many scientists have long argued that CPT has been wrongly neglected, both as a therapy for emerging diseases and in preparation for future unknown threats. Today, the approach is gaining ground. Trials of convalescent plasma are beginning for the treatment of patients with MERS, which has infected 938 people and killed 343 of them since it was discovered in 2012. And an international protocol aimed at removing hurdles to quickly rolling out trials of convalescent plasma has recently been drafted.

CPT Where and When ?


Convalescent plasma was found to effectively treat diphtheria and tetanus at the end of the nineteenth century, and was widely used in the first half of the twentieth century to treat diseases such as measles, mumps and pneumonia. But it fell off the radar after the development of antibiotics, antiviral drugs and vaccines. (An exception was the adoption of CPT in Argentina for Argentine hemorrhagic fever after a successful controlled trial in the 1970s.)

When available , vaccines and drugs are the best option. CPT is a lengthy and risky procedure, and may be not able to cover a large population with ease. In other case , drugs and vaccine can be mass produced and easily applied during and out break.

CPT is more complicated — it requires collecting survivors’ blood, screening it for pathogens and then organizing patient transfusion. And standardizing batches of plasma is difficult, because antibody levels in donated blood can vary widely.

But an epidemic or pandemic of a new pathogen turns that logic on its head. As in the case of the Ebola epidemic, there are typically no drugs or vaccines available, and developing these usually takes years. By contrast, “convalescent plasma is one of the few things you can get up and running quickly”, says Calum Semple, a paediatrician and clinical virologist at the University of Liverpool, UK, who is involved in the Guinea Ebola trial. Trials for Ebola and other emerging diseases “should have happened years ago”, he adds. He points out that the therapy is often considered old-fashioned and that there are neither big profits to be made nor cutting-edge-science interests at stake. “Convalescent plasma is not attractive to pharma, or the modern model of academia,” he says.

Adequate screening for pathogens in donated blood can be an issue in poorer countries. In the CPT Ebola trials, a chemical is being added to the donated blood. When the mixture is exposed to ultra­violet light, the compound irreversibly crosslinks the DNA and RNA of pathogens, preventing their replication.

Hope advancement in CPT may bring control over new epidemic outbreaks. Hope the human race may gain the ability to stand with their own mistakes.

EBOLA treatment: Convalescent plasma therapy (CPT) Gaining Momentum

Sunday, December 28, 2014

WhatSapp For Desktops

Just Heard WhatsApp Coming to Desktop O.o
WhatsApp is available on almost every mobile platform, including discontinued platforms like Symbian and Nokia Series 40, but has never developed a web client. New reports say WhatsApp will finally come to the desktop, after five years of availability. The new web client will use OAuth, sending a message to the mobile to verify to user on the web client.


Creating a web client has been on WhatsApp users wish-list for the past few years, even with the surge to mobile in developing nations, where WhatsApp is most popular. The web client should have extra functionality for the larger screen.

 Facebook has taken a mobile-first approach for its newest features, but still updates the web client regularly to keep up with new features. Facebook may have pushed WhatsApp to create a web client.
WhatsApp continues to be the dominant messaging app worldwide, with 650 million active users. WeChat, LINE, Viber, Skype and various other messaging platforms are all vying for attention.
It looks like Facebook wants to split the two messaging services, having WhatsApp in Asia and Facebook Messenger in the West. The social network does not seem keen to merge the two services together.

WhatsApp Coming to Desktop


Productive meetings - Steve Jobs




Justin SullivanAmerican businesses lose an estimated $37 billion a year due to meeting mistakes.

Steve Jobs made sure that Apple wasn't one of those companies.

Here are three ways the iconic CEO made meetings super productive.

1. He kept meetings as small as possible.


In his book "Insanely Simple," longtime Jobs collaborator Ken Segall detailed what it was like to work with him.

In one story, Jobs was about to start a weekly meeting with Apple's ad agency.

Then Jobs spotted someone new.

"He stopped cold," Segall writes. "His eyes locked on to the one thing in the room that didn't look right. Pointing to Lorrie, he said, 'Who are you?'"

Calmly, she explained that she was asked to the meeting because she was a part of related marketing projects.

Jobs heard her, and then politely told her to get out.

"I don't think we need you in this meeting, Lorrie. Thanks," he said.

He was similarly ruthless with himself. When Barack Obama asked him to join a small gathering of tech moguls, Jobs declined - the President invited too many people for his taste.


2. He made sure someone was responsible for each item on the agenda.


In a 2011 feature investigating Apple's culture, Fortune reporter Adam Lashinsky detailed a few of the formal processes that Jobs used, which led Apple to become the world's most valuable company.

At the core of Job's mentality was the "accountability mindset" - meaning that processes were put in place so that everybody knew who was responsible for what.

As Lachinsky described:

"Internal Applespeak even has a name for it, the "DRI," or directly responsible individual. Often the DRI's name will appear on an agenda for a meeting, so everybody knows who is responsible. "Any effective meeting at Apple will have an action list," says a former employee. "Next to each action item will be the DRI." A common phrase heard around Apple when someone is trying to learn the right contact on a project: "Who's the DRI on that?"

The process works. Gloria Lin moved from the iPod team at Apple to leading the product team at Flipboard - and she brought DRIs with her.

They're hugely helpful in a startup situation.

"In a fast-growing company with tons of activity, important things get left on the table not because people are irresponsible but just because they're really busy," she wrote on Quora. "When you feel like something is your baby, then you really, really care about how it's doing."

3. He wouldn't let people hide behind PowerPoint.


Walter Isaacson, author of the "Steve Jobs" biography, said, "Jobs hated formal presentations, but he loved freewheeling face-to-face meetings."

Every Wednesday afternoon, he had an agenda-less meeting with his marketing and advertising team.

Slideshows were banned because Jobs wanted his team to debate passionately and think critically, all without leaning on technology.

"I hate the way people use slide presentations instead of thinking," Jobs told Isaacson. "People would confront a problem by creating a presentation. I wanted them to engage, to hash things out at the table, rather than show a bunch of slides. People who know what they're talking about don't need PowerPoint."

3 Ways Steve Jobs Made Meetings Insanely Productive - And Often Terrifying


The Memory


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Memory is an essential human skill, relied upon on as a second-to-second basis for survival, yet still mysterious and poorly understood. Here are 9 things we do know about it, that you’ll wish you knew sooner.

1. Memory is enhanced by forgetting things first.


Conventional wisdom says that if you want to remember something, you should repeat it often, and keep it fresh in your memory. Husband and wife research team Robert and Elizabeth Bjork out of UCLA suggest otherwise. According to their research,

You need to forget a new piece of information at some level before remembering it in order to make that memory robust over time.

The more a new memory fades before you go looking for it, the more it’s subsequent “retrieval strength” improves.

2. Memory thrives on storytelling.


In his 2012 bestseller, Moon walking with Einstein, Joshua Foer tells tall tales of memory champions recalling entire randomly shuffled decks of playing cards, from memory in less than a minute. How do they accomplish these miraculous feats? They get really good at telling memorable stories to themselves while weaving in what they’re trying to remember. Because the human brain is built for storytelling,

The more things you can link together into a narrative, the more readily you’ll be able to recall them later on.

3. Memory is supercharged when new information is visual.


What do we typically associate with learning new technical information? That’s right, textbooks. But the least effective component of textbooks may just be the “text” itself. Yes, we generally find it easier and faster to process information in visual form (if you’ve ever thought to yourself, “I’ll just wait for it to come out as a movie,” you know what I’m talking about). But does it help us learn better? Richard Mayer, psychology researcher at UCSB, indicates yes. His research demonstrates that:

Text paired with a relevant visual significantly improves the amount of information retained by novice learners.

4. Memory is made robust by a rich environment.


Some people swear they can write better in the coffee shop with the low hum of conversation. This may be true. As Benedict Carey indicates in his recent bestseller, How We Learn, a large body of psychology research shows that:

Studying in a diverse range of environments can actually improve the robustness of your ability to recall that information in the future.

It turns out, “find a quiet place to concentrate” may not be the best advice if you’re trying to build a memory that will stand the test of time.

5. Memory is not all about repetition.


You’ve heard it before: “Practice makes perfect.” In reality, this common phrase should be updated to say: “A specific type of difficult practice makes perfect.” Back to the Bjork research team again – they found that:

Repetition is key, but is most powerful when “interleaved” with unrelated information to make the brain work harder.

This forces us to have to go back and “retrieve” that information from our long-term memory stores each time we do it, strengthening that neural connection for future use much more than simply repeating something over and over (which offloads some of the work to your short-term memory). So when it comes to practice, there is a level of “desirable difficulty,” as they call it, to any task that will make it much easier to recall in the future.

6. Memory uses procrastination as an important tool.


How many times have you gotten frustrated with yourself for procrastinating on an important assignment? Well don’t get too upset, because research indicates that procrastination is actually an important tool for getting things done. When we’re not actively focusing on something, it allows your subconscious to work on ideas in the background while you do other things. This effect is particularly noticeable during menial tasks (ever wonder why you get so many eureka moments in the shower?) and sleep. Bottom line:

Your brain needs time to integrate new ideas with existing memory, allowing them to percolate and connect.

7. Memory relies on your brain to “fill in the gaps.”


When a memory gets stored in your brain you retain its key features (the shape of someone’s face, what shoes they were wearing, how hard the wind was blowing), but most else is pretty much a blur. But what happens when someone asks you what the clouds looked like that day?

When faced with a fuzzy aspect of a memory (or one that wasn’t actually stored in the first place) your brain tends to “fill in the gaps” with what it “thinks” most probably was the case.

That’s why eye-witness accounts are so unreliable. Each time a witness is asked to describe what they saw (apart from the fact that people tend to see what they want to see), their memory is immediately contaminated with new information that is being transplanted into the past.

8. Memory gets broken up in bits and pieces in different parts of your brain.


The most common analogy for information storage in the brain is that of a computer. A new string of bits gets written in a particular location, and stored in the hard drive. Turns out, that’s not really how it goes.

Your memory is more like a distributed filing system.

Smells go over here. Emotional intensity goes down there. Visual information gets stored here. And then it’s the job of the hippocampus to pull everything back together. To remember it in the same way your brain has to pull everything back together, like a puzzle.

9. Memory gets prioritized by emotion.


Ever wonder why your most vivid childhood memories usually involve an intense emotion (fear, rejection, elation, pride)? As John Medina, author of Brain Rules explains:

Emotions “attach themselves” to new information in the brain, acting as an indicator of importance.

The stronger the intensity, the more clearly and readily you’ll be able to recall that memory.

9 Facts About Your Memory That You Won’t Believe You Didn’t Know

Air Asia flight QZ 8501 travelling from Indonesia to Singapore has gone missing - reports

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Air Asia flight missing - reports BBC BREAKING NEWS

Saturday, December 27, 2014


Eruptions, comets and a see-through mouse all captured the imagination in 2014

By Nature
Incredible discoveries in 2014 arose from researchers' relentless pursuit of answers about the world. From the far reaches of space to the depths of the oceans, Nature's selection of this year's most striking images document both natural disasters and technological wonders.

A FURIOUS FISSURE

Dawn and dusk in Iceland turned blood red earlier this year as volcanic pollution filled the skies. The Holuhraun fissure — near the erupting Bárðarbunga volcano — belched out thousands of tonnes of sulphur dioxide every day, surprising scientists who were expecting ashy expulsions similar to the Eyjafjallajökull eruption in 2010.


MOON MOSAIC

Jupiter's moon Europa, as it would look to human eyes. NASA reprocessed a series of images taken by the Galileo space probe in the late 1990s, adjusting the colours to create this realistic, high-resolution view of the moon's icy terrain.


VOLCANO TRAGEDY

Mount Ontake, an active volcano some 200 kilometres west of Tokyo, has long been a popular tourist destination in Japan. Despite careful monitoring by scientists, an eruption on 27 September caught many off guard, spraying ash and debris over the surrounding region and killing more than 50 people. Rescue teams battled thick ash to search for survivors in remote lodges near the mountain's peak.


DUMBO AT DEPTH

Tentacles coiled in a pose never seen before, this ‘dumbo octopus’ of the genus Grimpoteuthis was captured on camera in April in the Gulf of Mexico. Researchers on the US vessel Okeanos Explorergot this rare glimpse of the creature by piloting a remote-controlled submersible to a depth of some 2,000 metres.


PHILAE IN FLIGHT

The world was on tenterhooks in November as the European Space Agency’s Rosetta spacecraft attempted to put the Philae lander on the surface of comet 67P/Churyumov–Gerasimenko. Before successfully completing the tricky manoeuvre, Philae sent back this picture of itself closing in on its target as they both moved through space at more than 50,000 kilometres per hour.


EXTREME ARCHAEOLOGY

The 12,000-year-old skull of a teenager from Mexico sits on a rotating platform, enabling divers to take a three-dimensional scan of the remains. Found deep inside submerged caves in Mexico’s Yucatán Peninsula, the skull is part of a remarkable collection of ancient bones that are helping to shed light on how humans spread across the Americas. Difficulties in removing the remains meant that divers had to analyse them in situ.


EYE TO EYE

These staring eyes of a Phidippus audax jumping spider secured third place in Nikon’s Small World photography competition for Noah Fram-Schwartz of Greenwich, Connecticut.


THE SEE-THROUGH MOUSE

Why scan bodies if you can just make tissue transparent? This mouse has been rendered see-through by a team in Japan using a chemical cocktail and computational imaging, one of a growing number of methods that reveal organs without dissection.


ABOVE THE CLOUDS

It remains unclear why Japanese artist Azuma Makoto attached a bonsai tree to a balloon and launched it into the upper layers of the atmosphere. But the result of his ‘Exobiotanica’ project, which has now sent numerous plants into space, was a series of beautiful pictures like this one.


DROP EVERYTHING

These picolitre-sized silicone-oil droplets were snapped by researchers at the University of Twente in the Netherlands. Lighting up the droplets with 8-nanosecond-long laser pulses, the team took images 600 nanoseconds apart to capture how the falling droplets formed.


SHINE ON

The eerie green glow in this image from Emas National Park in Brazil emanates from the bioluminescence of click-beetle larvae living on a termite mound — and from the flight paths of adult beetles. Photographer Ary Bassous’s long exposure made him the winner in the invertebrates category of this year’s Wildlife Photographer of the Year competition, run by London's Natural History Museum and BBC Worldwide.

365 days: Images of the year 2014


Simplifying The Energy Needs For The Future



Photo: Shah Tissue Engineering and Additive Manufacturing Lab and Northwestern University


Making ceramic fuel cells with a 3-D printer would be a quick and easy way to manufacture the devices and could lead to new fuel cell designs that do a better job of converting a gas into electricity, according to researchers at Northwestern University.

The lab of Ramille Shah, assistant professor of materials science and engineering, has developed new inks that a single 3-D printer can use to create the individual components of the solid oxide fuel cell—cathode, anode, electrolyte, and interconnects. The inks are a mixture of ceramic particles that make up 70 to 90 percent of the mix, a binder, and a cocktail of solvents that evaporate at different rates. The ink for the electrolyte, for example, is made of yttrium-stabilized zirconia (YSZ) particles, while the anode is YSZ plus nickel oxide.

When the machine prints a line with one of these inks, a highly volatile solvent in the mix evaporates immediately, so the printed piece turns from a liquid to a solid instantly. The other solvents, however, evaporate more slowly, leaving the printed line hard enough to maintain its shape but soft enough that the next layer melds with it to form a single piece. The printing is done at room temperature, but just like when making a ceramic vase, the printed piece has to be fired at up to 1250° C to make it denser and smoother. To make sure the different parts of the printed fuel cell all shrink at the same rate during firing, the team tweaks the composition of the individual inks, and adds iron oxide in some layers.

“We can get really densely packed particles in the printed structure,” says Adam Jakus, a Ph.D. student in Shah’s lab, who described the work at the Materials Research Society’s fall meeting in Boston this week.

Solid-oxide fuel cells operate at high temperatures, so they don’t require catalysts and work with a variety of gases, including methane. They could be used to provide power to the electricity grid.

Using 3-D printing to build fuel cells of a standard design could be an easier manufacturing process than having to join the separate parts together, says Jakus. But, he says, the real promise could come from 3-D printing’s ability to create shapes that standard manufacturing processes can’t. For instance, they’ve printed flat sheets of the ceramic materials, which can be rolled or folded into different shapes before firing. Instead of the standard stack of fuel cells, they could be built in concentric circles, or be interwoven, creating more surface area and therefore easier transport of charge. Jakus, though, focuses on the inks, and will leave it up to colleagues who are experts in fuel cells to experiment with new designs.

Meanwhile, he’s developing similar inks for other uses, such as 3-D printed ceramic bone replacements that mimic the mechanical properties of actual bone. The team has also made an ink that allows 3-D printing of graphene.

Engineers Invent Inks for Making 3-D Printed Fuel Cells

This is How Jaguar Wants to Make Blind Spots Disappear



Jaguar's getting into the vaporware game with this augmented reality windshield concept, but the fundamental idea is sound … and really cool. Jaguar imagines that instead of a small area for a HUD, images could be projected on the whole windshield. This is what Jaguar thinks its Virtual Windscreen concept might look like in function, and the video below shows three interesting applications of the technology.


First, there are the racing and braking line overlays—you're familiar with these if you've ever played a console racing game with the assists on. As in the game world, this could be a nice, safe introduction to a new course, and one that wouldn't put an instructor at risk. Next, there are the ghost car overlays, also familiar from racing games. Lastly, the virtual cone function is a neat idea and could be a helpful training tool. Imagine a very fast straight and an unfamiliar car; perhaps a nice virtual cone chicane could help keep things under control without having to physically alter the course.



A few months ago, Jaguar showed off a virtual windscreen concept that brought displayed the sort of information overlays normally seen in racing games on a physical windshield via a head-up display.

Think braking lines, race-competitor names and times, and a lap timer—all projected onto the glass. This is where Jaguar Land Rover's head is at, and so plans to cook up a "virtually transparent" A-pillar shouldn't come as much surprise.


The technology at the core of the "virtual urban windscreen", as JLR calls it, is much the same—projected overlays on the windshield track objects of interest—in this case a pedestrian at risk of getting hit—and highlights them for the driver.

The new bits here are the screens embedded in the A-pillars, which allow the system to track and project a warning halo around the object even as it passes behind the pillar and onto the windshield.

External cameras capture the images displayed on the pillars. Think of it as n evolution of the sort of tech you may have seen already in the form of around-view monitors that stitch multiple camera views together to create a comprehensive overhead POV.



Other neat details in this demonstration are transparent B-pillars for over-the-shoulder lane checks, HUD overlays showing POIs, traffic-light countdown timers, and "follow me" ghost-car navigation guidance that replaces arrow-based navigation cues.

This is a research project, not a demonstration of existing technology, which is why it's rendered in CGI just like the original virtual windscreen concept.

Jaguar is looking into the technology but there's no word as to whether a real-world demonstrator has been constructed yet. Hopefully, Jaguar invests enough to get this off the ground, because anything that helps keep drivers' eyes up and on the road is welcome.

The Virtual Screen OF Jaguar


The Flying Drones And The Future

The sky may look very different in a few decades. This week’s Big Future takes a look at how the world will change as drone technology spreads, filling the world’s rooftops and skies. Tech giants like Amazon and Google are testing them out as delivery robots, but those early implementations are just scratching the surface.


A flying security guard


Companies like Skycatch are currently developing drones that could act as automated guard dogs. When a motion detector is triggered, the drone would take flight and check out the scene, beaming back a live video feed so you can decide whether to follow up with a call to the police or even an onboard weapon.


An eye in the sky


The Supreme Court has ruled that citizens have no expectation of privacy when it comes to aerial filming — so for the time being, camera drones are fair game. It’s easy to imagine tabloids using them as propeller-powered paparazzi, tasked to follow a celebrity’s every move around town.


Be the drone


Things really get wild when you start to combine drones with virtual reality. Add an Oculus Rift to a quadcopter with an HDMI output and you can experience a drone’s-eye-view of a race over a raging river or inside an active volcano.

The Big Future: How will drones change the skies?

Friday, December 26, 2014

A new firmware build with Android 5.0 update has been released for Galaxy S5.Samsung
Samsung has rolled out the third Android 5.0 Lollipop firmware update with build G900FXXU1BNL9 for the international European version of Galaxy S5 with model number SM-G900F. Like the previous two updates G900FXXU1BNL2 and G900FXXU1BNL7, the recent release is for the Galaxy S5 users in Poland. 
As per the changelog, build G900FXXU1BNL9 improves the performance of the device. You can get the stock firmware update through OTA and via the Samsung Kies server.

But, if for some reason you failed to update your Galaxy S5 to G900FXXU1BNL9 using either of the official methods, you can still install the firmware manually using the Odin flashing tool.
Firmware details
Model: SM-G900FModel 
name: Galaxy S5
Country: Poland
Version: Android 5.0
Changelist: 77433514
Build date: 18 December
Product Code: XEOPDA: G900FXXU1BNL9CSC: G900FXEO1BNL1MODEM: G900FXXU1BNL9
If you want to keep your Galaxy S5 updated with the latest firmware, check out our following installation method. Keep in mind that G900FXXU1BNL9 is an unbranded version of firmware and can be installed on any unlocked SM-G900F unit, irrespective of country and region.
Pre-requisites
Install USB Drivers for Galaxy S5 to connect the Android device with the computerEnable USB Debugging Mode on phone to connect it with the computer and use Android SDK with it. [Navigate to Settings>> Developer Options>> check the USB Debugging option.]As the tutorial is likely to wipe out all data of the phone, create a backup using custom recoveryVerify that the battery level of the Galaxy S5 is above 80%You should be having an unlocked version of Galaxy S5 SM-G900F unitThe phone will lose custom ROM with the installation of official firmware. Also, the custom recovery will be replaced by the stock versionThe device will no longer belong to a rooted version with the installation of official firmwareG900FXXU1BNL9 Android 5.0 stock firmware works only with Galaxy S5 SM-G900F. As flashing this on any other variant might brick the device, verify the model number by navigating toSettings>> About phone>> Model numberIBTimes UK will not be held liable for any damage to the device
Download files
How to install G900FXXU1BNL9 Android 5.0 official update on Galaxy S5 G900F
Step-1: Extract the downloaded firmware zip using any extracting tool to get a .tar.md5 file with a few other files, which are optional
Step-2: Extract the Odin zip to get Odin3 v.3.09.exe with a few other files
Step-3: Power off the Galaxy S5
Step-4: Put the phone into Download Mode by pressing and holding HomePower and Volume Down button together
Note: Ensure that you have installed proper USB drivers installed on your PC
Step-5: Run Odin as Administrator on the computer. For this, click on the tool then right-click and select Run as Administrator from the drop down menu
Step-6: Connect Galaxy S5 to the PC using USB cable while it is in Download mode. Wait for some time until Odin detects the device. When the phone is connected successfully, the ID: COM box in Odin will turn light blue with COM port number. This step might take some time
Step-7: In Odin, click AP button and select the firmware file with .tar.md5 extension
Step-8: Enable Auto Reboot and F.Reset Time checkboxes in Odin. Ensure Re-Partition checkbox is not checked
Step-9: Double check everything and click theStart button in Odin. The installation process should begin now and take a few minutes to complete
Step-10: When the process is completed, the phone will restart automatically. Once the home screen appears on the phone, disconnect the phone from the computer
Now, you should have the latest Android 5.0 firmware on your Galaxy S5. Head over to Settings>> About phone to verify the new software version.

Galaxy S5 receives new Android 5.0 G900FXXU1BNL9 firmware with performance improvement [How to Install]

Thursday, December 25, 2014

The World OF USB Chargers


When you buy a USB charger, how do you know if you're getting a safe, high-quality charger for your money? You can't tell from the outside if a charger provides silky-smooth power or if it is a dangerous charger that emits noisy power that cause touchscreen malfunctions[1] and could self-destruct. In this article, I carefully measure the performance of a dozen different chargers, rate their performance in multiple categories, and determine the winners and losers.
The above picture shows the twelve chargers I analyzed.[2] The charger in the upper-left is the cube-shaped Apple iPhone charger. Next is an oblong Samsung adapter and a cube Samsung adapter. The Apple iPad power adapter is substantially larger[3] than the iPhone charger but provides twice the power. The HP TouchPad power charger has an unusual cylindrical shape. Next is a counterfeit iPhone charger, which appears identical to the real thing but only costs a couple dollars. In the upper right, the Monoprice iPhone charger has a 30-pin dock connector, not USB. The colorful orange charger is a counterfeit of the Apple UK iPhone charger. Next is a counterfeit iPad charger that looks just like the real one. The Belkin power adapter is oval shaped. The KMS power supply provides four USB ports. The final charger is a Motorola Charger.

Summary of ratings

The chargers are rated from 1 to 5 energy bolts, with 5 bolts the best. The overall rating below is the average of the ratings in nine different categories, based on my measurements of efficiency, power stability, power quality, and power output. The quick summary is that phone manufacturers provide pretty good chargers, the aftermarket chargers are worse, and $2 counterfeit chargers are pretty much junk. Much to my surprise, the HP TouchPad charger (which isn't sold any more) turned out to have the best overall score. The counterfeit iPhone charger set a new low for bad quality, strikingly worse than the other two counterfeits.
 ModelOverall rating

Apple iPhone

Apple A1265

Samsung oblong

Samsung travel adapter ETA0U60JBE

Samsung cube

Samsung travel adapter ETA0U80JBE

Apple iPad

Apple 10W USB Power Adapter A1357

HP TouchPad

Hewlett Packard LPS AC/DC Adaptor P/N 157-10157-00

Counterfeit iPhone

Fake Apple A1265 "Designed by California"

Monoprice

Monoprice Switching Mode Power Supply MIPTC1A

Counterfeit UK

Fake Apple A1299

Counterfeit iPad

Fake Apple 10W USB Power Adapter A1357

Belkin

Belkin UTC001

KMS

KMS-AC09

Motorola

Motorola AC Power Supply DC4050US0301

Inside a charger

These chargers cram a lot of complex circuitry into a small package, as you can see from the iPhone charger below. (See my iPhone charger teardown for more details.) The small size makes it challenging to make an efficient, high-quality charger, while the commoditization of chargers and the demand for low prices pressure manufacturers to make the circuit as simple as possible and exclude expensive components, even if the power quality is worse. The result is a wide variation in the quality of the chargers, most of which is invisible to the user, who may believe "a charger is a charger".
The circuitry inside the Apple iPhone USB charger
Inside the iPhone charger
Internally a charger is an amazingly compact switching power supply that efficiently converts line AC into 5 volt DC output. The input AC is first converted to high-voltage DC. The DC is chopped up tens of thousands of times a second and fed into a tiny flyback transformer. The output of the transformer is converted to low-voltage DC, filtered, and provided as the 5 volt output through the USB port. A feedback mechanism regulates the chopping frequency to keep the output voltage stable. Name-brand chargers use a specialized control IC to run the charger, while cheap chargers cut corners by replacing the IC with a cheap, low-quality feedback circuit.[4]
A poor design can suffer several problems. If the output voltage is not filtered well, there will be noise and spikes due to the high-frequency switching. At extreme levels this could damage your phone, but the most common symptom is the touchscreen doesn't work while the charger is plugged in.[1] A second problem is the output voltage can be affected by the AC input, causing 120 Hz "ripple".[5] Third, the charger is supposed to provide a constant voltage. A poor design can cause the voltage to sag as the load increases. Your phone will take longer to charge if the charger doesn't provide enough power. Finally, USB chargers are not all interchangeable; the wrong type of charger may not work with your device.[6]

Counterfeits

Counterfeit chargers pose a safety hazard as well as a hazard to your phone. You can buy a charger that looks just like an Apple charger for about $2, but the charger is nothing like an Apple charger internally. The power is extremely bad quality (as I will show below). But more importantly, these chargers ignore safety standards. Since chargers have hundreds of volts internally, there's a big risk if a charger doesn't have proper insulation. You're putting your phone, and more importantly yourself, at risk if you use one of these chargers. I did a teardown of a counterfeit charger, which shows the differences in detail.
I've taken apart several counterfeit chargers and readers have sent me photos of others. Surprisingly, the counterfeit chargers I've examined all use different circuitry internally. If you get a counterfeit, it could be worse or better than what I've seen.
How do you tell if a charger is counterfeit? The fakes are very similar; it's hard for me to tell, even after studying many chargers. There's a video on how to distinguish real and fake chargers through subtle differences. You can also weigh the charger (if you have an accurate scale), and compare with the weights I give above. The easiest way to get a genuine Apple charger is fork over $29 to an Apple store. If you buy a $2 "Original Genuine Apple" charger on eBay shipped from China, I can guarantee it's counterfeit. On the other hand, I've succeeded in buying genuine used chargers from US resellers for a moderate price on eBay, but you're taking a chance.
The following picture shows a counterfeit charger that burned up. The safety issues with counterfeits are not just theoretical; when hundreds of volts short out, the results can be spectacular.
Counterfeit iPhone charger that burned up
Photo by Anool Mahidharia. Used with permission

Indicated charger type

A device being charged can detect what type of charger is being used through specific voltages on the USB data pins.[6] Because of this, some devices only work with their own special chargers. For instance, an "incorrect" charger may be rejected by an iPhone 3GS or later with the message "Charging is not supported with this accessory".[7]
There are many different charger types, but only a few are used in the chargers I examined. A USB charger that follows the standard is known as a "dedicated USB charger". However, some manufacturers (such as Apple, Sony, and HP) don't follow the USB standard but implement their own proprietary charger types. Apple has separate charger types for 1 amp (iPhone) and 2 amp (iPad) chargers. HP has a special type for the HP TouchPad.
The point is that USB chargers are not interchangeable, and devices may not work if the charger type doesn't match what the device expects. The table below shows the type of charger, the current that the label claims the charger provides, the current it actually provides, and the charger type it indicates to the device.
The types of the counterfeit chargers are a mess, as they advertise one power level, actually supply a different power level, and have the charger type for a third level. For example, the counterfeit iPhone charger is advertised as supplying 1 amp, but has the 2A charger type, so an iPad will expect 2 amps but not obtain enough power. On the other hand, the counterfeit iPad charger claims to supply 2 amps, but really only supplies 1 amp and has a 1A type.
 Charger typeLabelMeasured currentWeight
Apple iPhoneApple 1A charger5V 1A1.79A23.0g
Samsung oblongdedicated USB charger5V 0.7A.80A33.1g
Samsung cubededicated USB charger5V 1A1.17A23.2g
Apple iPadApple 2A charger5.1V 2.1A2.3A67.5g
HP TouchPadHP TouchPad charger5.3V 2.0A2.4A54.8g
Counterfeit iPhoneApple 2A charger5V 1A.94A18.8g
MonopriceApple dock5V 1A1.22A67.8g
Counterfeit UKdedicated USB charger5V 1A.57A29.4g
Counterfeit iPadApple 1A charger5.1V 2.1A1.2A43.4g
BelkinApple 1A charger5V 1A1.27A43.0g
KMSApple 2A charger5V 2.1A3.4A99.5g
Motoroladedicated USB charger5.1V .85A.82A38.6g

Efficiency

People often wonder how much power their charger is wasting while it's idle, and if they should unplug their charger when not in use. I measured this "vampire" power usage and found the chargers varied by more than a factor of 20 in their idle power usage. The Samsung oblong charger came in best, using just 19 mW; this was so low compared to the other chargers that I measured it again a different way to make sure I hadn't made an error. On the other extreme, the fake iPhone charger used 375 mW. The Apple iPhone charger performed surprisingly badly at 195 mW. If plugged in for a year, this would cost you about 21 cents in electricity, so it's probably not worth worrying about.[8] In the following table, I use the official charger Star Rating System (yes, there actually is such a thing).[9][10]
I also measured efficiency of the chargers under load.[11] One of the benefits of switching power supplies over simpler linear supplies is they are much more efficient at converting the input power to output. The chargers I measured all did pretty well, with 63% to 80% efficiency. The HP charger was the winner here.
 VampiremilliwattsEfficiencyPercent
Apple iPhone19574
Samsung oblong1976
Samsung cube8677
Apple iPad6278
HP TouchPad9180
Counterfeit iPhone37563
Monoprice7872
Counterfeit UK10363
Counterfeit iPad9566
Belkin23466
KMS17969
Motorola5975

The chargers up close

Apple iPhone and counterfeit

A real Apple iPhone charger (left) and a counterfeit charger (right
The above photo shows a real iPhone charger (left) and a counterfeit (right); the two chargers are almost identical, down to the green dot. If you look closely, the genuine one says "Designed by Apple in California", while the counterfeit has the puzzling text "Designed by California". The counterfeit also removed the "Apple Japan" text below the plug. I've seen another counterfeit that says "Designed by Abble" (not Apple). I assume the word "Apple" is removed for legal or trademark reasons, since the word "Apple" is often (but not always) missing from counterfeits.

Samsung oblong

The Samsung oblong charger.
I call this charger the Samsung oblong charger, to distinguish it from the Samsung cube charger.

Samsung cube


The Samsung cube charger is shaped very similarly to the Apple iPhone charger. Internally, however, it turns out to be entirely different.

Apple iPad and counterfeit

A real Apple iPad charger (left) and a counterfeit charger (right
The photo above shows a real iPad charger (left) and a counterfeit (right). The counterfeit has almost identical text, but without "Designed by Apple in California. Assembled in China", "Listed" under UL, and the manufacturer "Foxlink". Inexplicably this sanitization left "TM and © 2010 Apple Inc".
Real (left) and counterfeit (right) iPad chargers
The above photo shows a real iPad charger on the left and a fake iPad charger on the right, with the plug removed. The most visible difference is the real charger has a round metal grounding post, while the fake has plastic. (The US plug isn't grounded, but in other countries the lack of ground in the counterfeit could pose a safety hazard.)

HP TouchPad

HP TouchPad charger HP TouchPad charger
The HP TouchPad charger has a very unusual cylindrical shape, which is striking if perhaps not practical. The charger twists apart, allowing the plug to be replaced for different countries. (It took me weeks to discover this feature.)

Monoprice

Monoprice USB charger
The Monoprice charger isn't a USB charger, but instead has a 30-pin iPhone dock connector attached. It is a relatively large charger.

Counterfeit UK

Counterfeit Apple UK iPhone charger
This charger is a counterfeit of the Apple UK iPhone charger. They've removed Apple from the text, but left Emerson Network Power, which I'm sure is not the actual manufacturer. The genuine Apple UK charger can be distinguished by a serial number inside the USB connector.

Belkin

Belkin phone charger
The Belkin charger eschews the minimal design styling of most chargers, with a roughly oval cross section, curves and ribs, and a cover over the USB port.

KMS

KMS 4-port USB charger with plug detached
The KMS charger is unusual in providing 4 USB ports. It also gives off a blue glow while in use. The plug can be removed and replaced for use in different countries, similar to the iPad and HP TouchPad chargers. I couldn't find any UL safety approval on this charger, but I did find a report of one catching fire.

Motorola

Motorola phone charger
The Motorola charger has the lowest listed power output, 850mA. The back of it has a holographic sticker (like a credit card), which may ward off counterfeiters, even though it's unlikely for anyone to counterfeit this charger. I wonder though why Apple doesn't use holograms or other anti-counterfeiting techniques, given the large number of counterfeit Apple chargers being sold.

Delivery of advertised power

Each charger has an advertised power output, but some chargers produce considerably more and some produce much less. Your device will take longer to charge, if the charger can't put out enough power. This table shows each charger's ability to deliver the rated power, based on my measurements of maximum power. While most chargers meet or exceed the power rating, there are some exceptions.
The counterfeit chargers perform extremely poorly, putting out a fraction of the expected power. Charging your device with one of these chargers will be a slow, frustrating experience. In particular, the counterfeit UK charger only produces a third of the expected power. Although the label claims the charger works on 100-240 volts, it's clearly not designed to work on US power.
The iPad is a surprise, putting out less power than expected. Despite being nominally a 10 watt charger, the label says it provides 5.1V and 2.1A, which works out to 10.7 watts. However, the maximum power I measured is 10.1 watts (4.4 volts at 2.3 amps, as shown in the Power section below). Since the measured power is slightly less than advertised, it only gets four bolts.
 RatingLabelWatts from labelMeasured watts
Apple iPhone5V 1A5.06.0
Samsung oblong5V 0.7A3.54.0
Samsung cube5V 1A5.05.5
Apple iPad5.1V 2.1A10.710.1
HP TouchPad5.3V 2.0A10.611.4
Counterfeit iPhone5V 1A5.02.7
Monoprice5V 1A5.05.7
Counterfeit UK5V 1A5.01.7
Counterfeit iPad5.1V 2.1A10.75.9
Belkin5V 1A5.05.6
KMS5V 2.1A10.510.9
Motorola5.1V .85A4.34.3

Power quality

In this section, I measure the quality of the power produced by the different chargers. I analyze it for voltage spikes, high frequency noise, and line-frequency ripple. The following table summarizes the results in three categories. Spikes indicates extremely brief large voltage spikes in the output, while Noise indicates high-frequency noise in the output, and Ripple indicates low-frequency (120 Hz) fluctuations in the output.[12]
 SpikesNoiseRipple
Apple iPhone
Samsung oblong
Samsung cube
Apple iPad
HP TouchPad
Counterfeit iPhone
Monoprice
Counterfeit UK
Counterfeit iPad
Belkin
KMS
Motorola
The following oscilloscope traces show the output signal (yellow) and frequency spectrum (orange). The left images provide high-frequency information on the output voltage. The right images show the low-frequency information on the output voltage.[13]
The desired voltage graph is a flat, thin yellow line indicating totally smooth power. However, some factors mess this up. First, any ripple from the power line will show up as 5 sinusoidal peaks in the first (high-frequency) yellow line. High-frequency noise will widen the yellow line. Voltage spikes will appear as vertical spikes in the yellow line.
The plots also show the frequency spectrum in orange, from 0 at the left to 230 kHz at the right. The desired graph would have the orange spectrum near the bottom of the screen. Thus, the power quality exponentially gets worse as the orange line gets higher. The left (high frequency) spectrum generally shows noise at the switching frequency of the charger (and harmonics). The right (low frequency) spectrum typically shows spikes at multiples of 120 Hz, caused by ripple from the 60 Hz power.[5]

Apple iPhone

High frequency oscilloscope trace from Apple iPhone charger Low frequency oscilloscope trace from Apple iPhone charger
The ripple is clearly visible as the waves in the yellow trace on the left and as the spikes (at 120 Hz and 240 Hz) in the orange trace on the right.
The iPhone charger performs extremely well at filtering out spikes and noise, the best of the chargers I measured. Apart from the 120 Hz spikes, the noise spectrum (orange) is flat and very low. The power quality is so good, I checked the results several times to make sure I wasn't missing something.

Samsung oblong

High frequency oscilloscope trace from Samsung oblong charger Low frequency oscilloscope trace from Samsung oblong charger
The Samsung charger's output has a lot more noise than the iPhone charger. This is visible in the thickness and jaggedness of the yellow output curves. The orange frequency spectrum on the left shows large peaks at harmonics of the switching frequency. The 120 Hz spike on the right is a bit lower than the iPhone charger, so the ripple filtering is a bit better.

Samsung cube

High frequency oscilloscope trace from Samsung cube charger Low frequency oscilloscope trace from Samsung cube charger
The Samsung cube charger shows some noise in the output (yellow). The frequency spectrum shows wide peaks at multiples of the the switching frequency, about 90kHz. There's some ripple.

Apple iPad

High frequency oscilloscope trace from Apple iPad charger Low frequency oscilloscope trace from Apple iPad charger
The iPad charger almost eliminates the ripple; only a small blip is visible in the orange spectrum on the right. The noise level is low, although appreciably worse than the iPhone.

HP TouchPad

High frequency oscilloscope trace from HP TouchPad charger Low frequency oscilloscope trace from HP TouchPad charger
There's no ripple visible in the HP charger spectrum on the right. The overall noise level is good.

Counterfeit iPhone

High frequency oscilloscope trace from counterfeit iPhone charger Low frequency oscilloscope trace from counterfeit iPhone charger
The output from this counterfeit charger is a wall of noise. In order to fit the waveform in the display, I had to double the scale on the left and increase it by a factor of 5 on the right, so the yellow curve is actually much worse than it appears. On the left, note the huge ripple with massive high-frequency noise on top. This output is not something you want to feed into your phone.

Monoprice

High frequency oscilloscope trace from Monoprice USB charger Low frequency oscilloscope trace from Monoprice USB charger
The output from this charger is very noisy, as you can see from the thickness of the yellow line. Note that the frequency spectrum (left) has very tall but narrow spikes at harmonics of the 28kHz switching frequency, showing a lot of high-frequency noise. On the positive side, there is hardly any ripple.

Counterfeit UK

High frequency oscilloscope trace from counterfeit UK iPhone charger Low frequency oscilloscope trace from counterfeit UK iPhone charger
This charger has very bad output. The large degree of ripple is visible in the waveform (yellow, left) and the very large spikes in the spectrum (orange, right). The thickness of the yellow waveform shows the large amount of high-frequency noise, which is also visible in the very high peaks in the spectrum (orange, left).

Counterfeit iPad

High frequency oscilloscope trace from counterfeit iPad charger Low frequency oscilloscope trace from counterfeit iPad charger
This counterfeit charger has so much noise in the output that I had to double the scale on the left to get it to fit. Note the very large spikes in the output (yellow). The spectrum (orange, left) is much higher everywhere, indicating noise at all frequencies. Surprisingly, it has only a moderate amount of ripple; the manufacturer seems to have done at least one thing right.

Belkin

High frequency oscilloscope trace from Belkin phone charger Low frequency oscilloscope trace from Belkin phone charger
The Belkin charger does well at eliminating ripple, but has a lot of noise otherwise. The spectrum (orange, left) shows large peaks. The yellow output is wide, showing a lot of noise, combined with many large voltage spikes of about 1/3 volt.

KMS

High frequency oscilloscope trace from KMS charger Low frequency oscilloscope trace from KMS charger
The KMS charger has fairly good output, with a small peak in the spectrum (orange, left) at the switching frequency. It has no detectable ripple. However, it has many large voltage spikes in the output, over half a volt, as can be seen on the right.

Motorola

High frequency oscilloscope trace from Motorola phone charger Low frequency oscilloscope trace from Motorola phone charger
The Motorola charger has a lot of spikes in the output (yellow) . The spectrum (orange, left) shows high frequency noise at the switching frequencies. There's a moderate amount of ripple (yellow, left and orange, right).

Summary

The quality of the output power is radically different between chargers. The counterfeit chargers are uniformly bad, with hardly any effort at filtering the output. The other chargers vary in quality with the iPhone charger setting the standard for noise-free power, but surprisingly poor filtering of ripple. The power quality is a key factor that affects the performance of chargers; spikes and noise are known to interfere with touchscreens.[1]

Power curve

In this section I look at the voltage and current output by the charger as the load increases. The first rating is Voltage Sag, which is the undesired drop in output voltage as the load increases. The second rating is Current Sag, which shows how the current fluctuates as load increases. Finally,Regulation shows the overall stability of the output from the charger.
 Voltage sagCurrent sagRegulation
Apple iPhone
Samsung oblong
Samsung cube
Apple iPad
HP TouchPad
Counterfeit iPhone
Monoprice
Counterfeit UK
Counterfeit iPad
Belkin
KMS
Motorola
The graphs in this section need a bit of explanation, which is provided in the diagram below. The voltage/current load curve shows the performance of the charger under different loads. Each point on the curve shows the current (X axis) and voltage (Y axis) produced by the charger under a particular load condition. Follow the yellow curve clockwise from the upper left to the lower left to see the effect of increasing load. The upper left point of the curve shows the voltage produced by the charger when there is no load on the charger. As the load increases, the charger is supposed to keep a constant voltage and increase the current (i.e. horizontal line), until it reaches the maximum power (upper right). If the load continues increasing, the charger switches to a constant current mode, dropping the voltage while continuing to provide the maximum current (i.e. vertical line).[14] At the lower right, the charger has reached its shutdown point due to excessive load, and rapidly drops to no output in the lower left corner to avoid damage.
Example Voltage vs Current graph for a phone charger

Apple iPhone

Voltage vs Current curve for Apple iPhone charger
The output from the Apple iPhone charger is surprisingly non-constant under load. The charger starts off with 5.2 volts with no load, dropping to 4.6 volts as the load increases, resulting in the downwards slope of the top yellow line. As the load increases, the current keeps increasing, resulting in the slope of the right yellow line. Note however that the yellow line is relatively thin, so the regulation is pretty good at each point.
Note that because this charger has a high current output, this chart has a different current (horizontal) scale than most of the charts to fit the whole trace in the image. Stretch it horizontally to compare with other graphs.

Samsung oblong

Voltage vs Current curve for Samsung oblong charger
For this charger, the voltage is approximately flat, except for a bump under no load (upper left) which is probably a measurement artifact. The vertical yellow line shows the current stays nearly constant as the load increases. The charger shows good voltage and current stability under changing load. The yellow line is a bit wider than the iPhone charger, showing a bit less regulation for a fixed load.

Samsung cube

Voltage vs Current curve for Samsung cube charger
The voltage curve sags slightly under load. The right hand curve shows the current stays stable, but the line is moderately wide, showing a bit of weakness in regulation.

Apple iPad

Voltage vs Current curve for Apple iPad charger
Similar to the iPhone charger, the iPad charger shows a lot of voltage sag. The voltage is about 5.1 V unloaded, dropping to 4.4 volts and 2.3 A (10.1 W) at the corner. Unlike the iPhone charger, the iPad charger has pretty good current stability. The regulation is solid, as shown by the narrowness of the yellow trace. Note the scale change due to the high current output.
I'm puzzled by the steep voltage sag on both the iPhone and iPad charger. Since the designers of the Apple charger went to a great deal of effort to build a high quality charger, I conclude they must not consider voltage sag worth worrying about. Or, more interestingly, maybe they built this sag as a feature for some reason. In any case, the chargers lose points on this.

HP TouchPad

Voltage vs Current curve for HP TouchPad charger
The charger has some voltage sag, but the current (vertical) is nice and constant. The yellow line is relatively thin, showing good regulation. Note the scale change due to the high current output.

Counterfeit iPhone

Voltage vs Current curve for counterfeit iPhone charger
This counterfeit charger shows extremely poor regulation, as shown by the very wide yellow line. It's hard to fit a voltage-current curve to this picture. The amount of power supplied by this charger seems almost random.

Monoprice

Voltage vs Current curve for Monoprice charger
The Monoprice charger shows reasonably straight voltage and current lines showing good constant voltage and current outputs. The vertical line shows some width and noise, suggesting the regulation isn't totally stable.

Counterfeit UK

Voltage vs Current curve for counterfeit UK iPhone charger
For this charger, the upper line doesn't get very far, showing that this charger doesn't output much current. My suspicion is that it was only tested with 240 volts so it performs poorly with 120 volts, even though the label says it takes 100 to 240 volts. The width of the yellow line shows very poor regulation.

Counterfeit iPad


The output of this counterfeit charger is so poorly regulated that it's hard to tell exactly what's happening with the voltage and current. It looks like the voltage is roughly constant underneath all the noise.

Belkin

Voltage vs Current curve for Belkin phone charger
The Belkin charger shows voltage sag as the current increases. In addition, the output is fairly noisy.

KMS

Voltage vs Current curve for KNS phone charger
The KMS charger shows a lot of voltage sag as the load increases. In addition, the output is all over the place, showing very poor regulation, more like what I'd expect from a counterfeit charger. Note the scale change due to the high current output.

Motorola

Voltage vs Current curve for Motorola phone charger
The Motorola charger shows a bit of voltage sag, but good current stability. The regulation is good but not perfect, as shown by the width of the yellow line. (The gaps in the vertical line are just measurement artifacts.) Note that the maximum current output of this charger is fairly low (as advertised).

Conclusions

So what charger should you spend your hard-earned money on? First, make sure the charger will work with your phone - for instance, newer iPhones only work with certain chargers. Second, don't buy a counterfeit charger; the price is great, but it's not worth risking your expensive device or your safety. Beyond that, it's your decision on how much quality is worth versus price, and I hope the data here helps you make a decision.

P.S. How about some teardowns?

My previous iPhone charger and fake charger teardowns were surprisingly popular, but if you were hoping for teardowns on the full set of chargers, you'll need to wait for a future blog post. I haven't torn the chargers apart yet; if I need to take more measurements, I don't want to have just a pile of parts. But I do have some preview pictures to hold you over until my teardown article.
Counterfeit Apple iPhone charger internals
The above picture shows the internals of a counterfeit Apple iPhone cube charger. The two boards stack to form the compact cube shape. This charger blatantly tries to pass as a genuine Apple charger; unlike the "Designed by California" charger, this one exactly copies the "Designed by Apple in California" text from the real charger. Note the very simple circuitry[4] - there are no components on the other side of the board, no controller IC, and very little filtering. Also look at the terrible mounting of the transistor on the front right; clearly the build quality of this charger is poor. Finally, note the overall lack of insulation; this charger wouldn't meet UL safety standards and could easily short out. But on the plus side, this charger only cost a couple dollars.
Inside a cheap USB charger
The above $2 charger is notable for its low-profile design; it's about as thin as you can make a charger and still fit the power prongs and the USB port. The transformer is very short to fit into this charger. Like the previous charger, it uses a very simple circuit,[4] has little filtering, and almost no safety insulation.
The complex circuit inside a Samsung cube USB charger Circuit boards of a Samsung cube USB charger, showing the transformer, switching transistor, filter capacitors, and other large components
Finally, the above pictures show the internals of the Samsung cube charger, which has circuit boards packed with tiny components and is much more advanced than the counterfeits (although slightly less complex than the Apple charger). Despite being very similar to the Apple charger on the outside, the Samsung charger uses an entirely different design and circuitry internally. One interesting design feature is the filter capacitors fit through the cut-out holes in the secondary circuit board, allowing the large filter capacitors to fit in the charger.

A dozen USB chargers in the lab: Apple is very good, but not quite the best

 
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