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It's a double whammy, because at cold temperatures the total capacity of the battery is reduced, and now they're only using 75% of that.

Also, recalls in lithium cobalt batteries are much, much more common than they are with other battery technologies, which is an issue inherent to the specific technology used for those batteries.


Lithium cobalt batteries have great specific power and energy, at a reasonable price per watt-hour, but there's a lot of trade-offs. It's been around a long time, so it's easy to manufacture.

Lithium iron phosphate batteries have lower specific power and energy, often making them too heavy for automotive use, but they have a great price per watt-hour, so they're getting enough use that they're becoming easier to manufacture, which is making them even more affordable and increasing the specific power and energy as new variations are developed.

Public transit busses are very large, don't carry a lot of weight, and need to charge and operate in cold areas, so sodium ion batteries are the best option, despite their low specific power and energy. They also theoretically have an even lower price per watt-hour, but they have so little adoption that there isn't any cost optimized manufacturing. They're absolutely what's needed for busses, and are also great for battery backup in cold climates, but as with lithium iron phosphate, it will take some time for them to be viable.

Early adopters are what makes technology happen, but they have to deal with under-performance and high costs. We may have to wait for the technology to mature, before it is practical for public infrastructure.


Video encoding and image compression is a huge use case, and not at all uncommon, so much so that a lot of hardware has dedicated hardware for it. Of course, offloading the SIMD instructions to dedicated hardware accelerators does reduce usage of SIMD instructions, but any time a specific CODEC or algorithm isn't accelerated, then the SIMD instructions are absolutely necessary.

Emulators also use them a lot, often in unintended ways, because they are very flexible. This is partially because the emulator itself can use the flexibility to optimize emulation, but also because hand optimizing with SIMD instruction can significantly improve performance of any application, which is necessary for the low-performance processors common in videogame consoles.


Also, the Knights Landing/Mill implementation is completely different from modern AVX-512. It's Ice Lake and Zen 4 that introduced modern AVX-512.

It doesn't need to be logged on to a Google account, and it supports locally storing map data and generating routes, so you could turn on network access, download local maps, block network access, then use it for navigation without it calling home.

There's also value in live traffic and road closure information.

That's a more difficult one, because that traffic data itself is aggregated from location sharing.

As long as copying some numbers, printed on a piece of plastic, into an online order form is all the authentication that is needed for a transaction, anything more than that is inherently security theater.

That’s why for most transactions I do with a credit card in my country, you need an extra validation with the mobile app. It is mostly American websites that do not enable this functionality.

Yes, because we don't want these stupid locked down apps. Credit cards give buyers many protections, it's very easy to dispute an illegitimate transaction.

However, you pay 2.7% for that convenience

The consumer does not typically pay this directly. It may be passed onto the consumer indirectly through higher prices, but those apply to anyone regardless of payment method. On the contrary, I get cash back on purchases and other rewards.

Pretty cool that you have a system where poor people pay for your fraud protection, cash back and rewards!

Europe mostly uses debit cards but also have most of those protections.

Because we have anti-fraud consumer potection rules and CCs operate on a make money first type of bais. The debit networks on the otherhand are a different story.

If it's QFN, you're probably best deadbugging it and jumpering all of the pins individually, but first make sure that you need the connection. QFP wireframes all have a center pad, whether or not it's electrically connected to the die or needed for thermal dissipation.

If it's an SO package, e.g. SSOP, TSOP, etc., Desolder the IC, add the jumper wire, bend the pins down enough to account for the thickness of the jumper wire, and resolder the IC.

Either way, make sure you have enough thermal mass connected to it for thermal dissipation. If there's components on the opposite side of the PCB, it's probably not much.


SATA ports are often rated for only tens to hundreds of cycles, so they're often made out of fallapartium.

If you're replacing one, it's easiest to cut all of the plastic off first, then desolder the contacts one at a time. Sometimes you can even pull the plastic off, without damaging it. It's usually necessary to preheat the board.


How are you burning yourself? I've only ever worked with one person who burned himself soldering when working on a SMT PCBs, and it was while desoldering a through-hole connector, when a desoldering station was long past its cleaning interval and it dripped some solder onto a metal ring he was wearing. This was a guy who would lick a soldering iron to see if it was hot and touch the molten solder in the wave solder machine. The Leidenfrost effect goes a long way.

My #1 way is from impatiently touching the board to see if it's cool enough to touch yet. That sounds dumb and it is.

More generally, with iron soldering only the iron and the last couple joints are hot. For SMD, there's more places for the heat to go; sometimes the entire board can be hot. Sometimes, you might need to balance being close enough in to get a good grip on the tiny parts, but far enough to not get burnt. You will feel the heat when SMD soldering - it's not always dangerous but another thing to pay attention to.


I have been impatient, and pulled a board out of the reflow oven while it's hot enough to burn, but it's fiberglass and resin, so it has very low heat transfer, giving enough time to put it down, without getting burnt.

I do a lot of soldering at my day job to bodge boards, tune networks, etc. I burn myself on the time because when I'm working through the microscope I seemingly forget I have hands or lose track of them and bump the iron into them when pulling it away from the work. Not sure why, but it's really easy for me to get into this mode where the view through the scope is the only thing in the world

An easy one is heat transferring through an SMD component to your tweezers, while trying to gently remove it from a heavy ground plane.

For boards with a bunch of layers and BGA/LGA packages, that have internal manufacturing errors or damage (e.g from overflexing), repairs can be untenable.

If the parts all have pads on their perimeter, then a jumper wire can replace internal traces. If the pads are underneath the part, and the trace is only internal, than a jumper may not be feasible, unless the damage happens from the surface in, in which case each layer can be jumpered at the damage.


>If the pads are underneath the part, and the trace is only internal, than a jumper may not be feasible.

BGa pad repairing is very common, here is one example: https://www.facebook.com/watch/?v=1077341457703029 (sorry can't find non-facebook link)


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