Update, October 12 22:32 —
Samsung has told Business Insider they are investigating what exactly went wrong with the Samsung Galaxy Note 7. The Korean manufacturer bodacious customers there would exist no issues after switching bombardment manufacturers and exchanging defective handsets, simply fifty-fifty replacement devices started burning up.
What went wrong? Will this be a trouble in time to come Samsung handsets? Nosotros hope not, merely we should know all the details “in the coming weeks”, when Sammy promises to release more data on their findings.
The replacement phones have batteries from a separate and different supplier than the original Note 7 devices. We’re currently conducting a thorough investigation, and it would exist premature to speculate on outcomes. We will share more data in the coming weeks.
Original, October 12 9:40 – With the end of Galaxy Note 7 production and the second call up echoing around the global media, it’southward going to accept Samsung some time to shake the harm that’s been washed to its manufacturing reputation. With the outset recall now clearly declining to address the Notation vii defect, there are a lot of questions to be answered nearly exactly what went wrong with the handset.
Samsung is still investigating the latest causes of Milky way Note vii fires, and we may never know the full story backside what is sure to be seen at the greatest blunder in smartphone history. Nevertheless, a few sources are already speaking out near the nigh probable factors behind these infamous fires and explosions.
Samsung permanently discontinues the Galaxy Note 7, $17 billion in sales lost
News
Bad batteries
Afterward the outset explosion reports, Samsung engineers concluded that the defect had exist acquired by defective batteries from one or more than of the companies suppliers. More than specifically, the company believed that these bad batteries had been designed by its own Samsung SDI segmentation, and that it would be safe to use batteries from its alternative supplier Amperex Technology Ltd (ATL).
The Samsung SDI designed batteries, which were manufactured in Vietnam and Republic of korea, were said to suffer from a manufacturing fault that could lead to a short excursion inside the cell. If even a modest short occurs within a lithium-ion battery, thermal delinquent can cause the jail cell to go along to heat upwardly, eventually leading to a burn down or explosion.
A new report by investigators points to similar manufacturing defects with ATL batteries every bit well
Samsung estimated that one in every 42,000 handsets suffered from the manufacturing mistake. The first global recall was initiated to supervene upon 2.v million handsets equipped with potentially lacking batteries with newly manufactured handsets with ATL cells. Unfortunately, this recall hasn’t stopped reports of exploding handsets coming in, leading to a full cease on Galaxy Note seven production.
A new report by investigators, seen by
Bloomberg, points to like manufacturing defects with the ATL batteries, which were supposed to be safe. The issue obviously crept into the supply line later on Samsung began replacing the Annotation 7, but it’south unknown how many devices are afflicted. Every bit a result, Samsung is recalling the 190,984 Annotation 7s that it sold in China every bit well.
Not enough space
In addition to the battery manufacturing trouble, an unpublished preliminary written report by Korea’southward Agency for Technology and Standards revealed that the company may have made a handset manufacturing fault that “placed force per unit area on plates contained within battery cells.”
The additional tension placed on the bombardment in models affected past the sub-optimized assembly could have led to the negative and positive poles coming into contact with each other, resulting in a bombardment breakdown and fires. This problem may accept been compounded by an insufficient layer of insulation between the positive and negative sides of the battery, which may crack or puncture under the boosted pressure. In other words, the express infinite inside the chassis may accept bent and cracked the within of the batteries.
Lithium-ion batteries establish in today’south smartphones are already densely stacked in layers to maximise battery capacity, just there’s even so a lot of competition for space inside handsets. Given the huge number of features packed inside the Galaxy Notation 7, including wireless charging circuitry, processor cooling pipes, and the new iris scanner, it’due south not difficult to believe that in that location was very lilliputian room for manufacturing errors in terms of internal space.
Co-ordinate to a person familiar with discussions between government agencies and Samsung, the SDI batteries from the first batch of Note 7s were indeed too large for the handset. Perhaps Samsung’s should have abandoned the 3.5mm jack for a few extra foursquare millimeters…
With reports of phones catching burn while turned off or unplugged, faulty batteries certainly sound similar a possible cause. Although this theory doesn’t fully explain why well-nigh reports of fires happened while the phone was part mode through charging.
The demand for faster charging
The Note 7 defect is now too reportedly linked to Samsung’s fast charging technology also. According to a
Financial Times
source who has spoken to Samsung executives, bug with the phone may have arisen from adjustments made to the processor in club to speed up bombardment charging times.
“If you try to charge the bombardment as well quickly information technology tin can make information technology more than volatile. If yous push an engine besides difficult, it volition explode. Something had to requite. These devices are miracles of technology — how much we can get out of that tiny piece of lithium-ion,”
Unfortunately, the source doesn’t brand it entirely clear how this type of problem would accept come virtually, or how changes made to the processor would affect the charging circuitry used to monitor and charge the li-ion battery.
Still, a piddling digging through a
ChipWorks
teardown reveals the use of a Dialog DA9155 charging scrap, alongside the familiar Proverb power IC. Importantly, this DA9155 does not appear to exist institute inside the Milky way S7 or S7 edge. This chip is a slave charger that extends the current capabilities of a master power IC for increased charging currents up to an boosted 2500mA. Information technology’s controlled by the awarding processor (AP) and, interestingly, kicks in during the high-ability abiding current charging phase.
Samsung appears to have supplemented its fast charging excursion with a slave buck converter for boosted current.
A read through the datasheet reveals that this flake features an AP programmable output current, switching frequency, and temperature monitor. As a slave device, programming and controlling the electric current and cooling is all left to the AP, which Samsung would have to program itself.
Careful consideration has to exist made non to exceed the battery’s charging electric current, optimize the switching frequency to the inductor charging circuitry for efficient power transfer, and monitoring the temperature of the bombardment. Furthermore, the DA9155M doesn’t force a chip reset until TJUNC_CRIT is triggered at 140°C, and then it’southward upwardly to the AP and Samsung’due south programmers to monitor lower temperatures and adjust ability commitment.
Of course, we don’t know how Samsung programmed its AP and this chip to command the battery charging characteristics, but it’s possible that engineers may have been using this IC to push the handset’southward fast charging capabilities to the bombardment’s limits. Although this does enhance the question of why this type of trouble couldn’t have been addressed with a firmware update, either by lowering the scrap’s current output or switching it off altogether.
That’southward only my own speculation based on the FT commodity though, it’s possible that the source is alluding to other changes fabricated to Samsung’s ability direction algorithms, the temperature monitoring system, or ane of the other four PMIC components institute inside the Note seven, which could be used to improve fast charging times.
Information technology’south certainly possible that fast charging power direction is just another contributing factor to a broader battery upshot and this information certainly goes some way to explaining why Samsung has halted production. This blazon of problem tin’t be fixed by simply exchanging batteries, it’s a deeper fault located inside Samsung’due south electronic hardware design.
A combination of factors
Despite weeks of testing, Samsung’s engineers have nonetheless not been able to repeatedly reproduce the fires and explosions, according to a report in the
New York Times. It appears that the company cannot exist certain exactly what the cause of the problem is, suggesting that the defect may not prevarication with any one individual component.
“[Samsung] was besides quick to blame the batteries; I recollect there was nix wrong with them or that they were non the main problem,”
– Park Chul-wan, former director of the Center for Advanced Batteries at the Korea Electronics Technology Institute
Allegedly, the corporate structure within the company has non helped sort out the problem either. Two quondam Samsung employees, who asked non to be named for fear of retaliation, described the workplace equally militaristic, with orders coming from higher management who didn’t necessarily empathize the bodily technologies inside the product. Furthermore, Samsung told employees to keep all communications almost its Notation 7 tests offline, significant that information exchanges between testers were severely hampered.
Samsung may have done the right thing by initiating a total call back and ending production of a handset with faults that still aren’t fully understood. Still, at that place will at present always be the lingering suspicion that the company may have been able to salvage the Note 7, had information technology taken more fourth dimension to ensure that the first think solved the issue.
Returning your Galaxy Note vii? Here are some other keen Android phones yous should check out
Features
It could take weeks, fifty-fifty months before Samsung and regulatory investigators understand the full cause, or causes, behind the various Milky way Notation vii fires. Nosotros will just take to await and see if Samsung ever officially reveals the defect that toppled the visitor’south otherwise greatest piece of mobile applied science.