Earlier quoted context omitted.
It depends. If you want to sleep well at night you take care. Of course if you are VW you take risks.
Taking a long time doesn't mean you've done more useful work.
But a longer testing can find more bugs.
Why Carmakers Can’t Transition to Newer Chips
251–260 of 335 posts
Re: Why Carmakers Can’t Transition to Newer Chips
#252The fine article quotes the Intel CEO: > "I’ll make them as many 16 nanometer chips as they want" However, > Carmakers have bombarded him with requests to invest in brand-new production capacity for semiconductors > featuring designs that, at best, were state of the art when the first Apple iPhone launched. He then says of that: > "It just makes no economic or strategic sense" So if we look at this from a capitalisti…
>automakers are not offering enough money to convince Intel to continue supplying their "old" types of chips
Like that time Apple was "not offering enough money to convince Intel to continue supplying their "old" types of chips" aka the StrongArm
Re: Why Carmakers Can’t Transition to Newer Chips
#253Earlier quoted context omitted.
>40-60V system What makes that voltage a better trade off?
Another factor I haven't seen mentioned in the responses yet is safety to human bodies. You (or your kid) can stick a wet finger in a 12V DC charger socket in your car and not get an electric shock, including any of the exposed contacts under the hood, including the battery terminals. But once you're up to 40-60V, the risk of electric shock to humans is actually something that needs to be factored in.
What amperage are we talking about here? Discussions of electrical safety solely in terms of voltage is nonsense.
Re: Why Carmakers Can’t Transition to Newer Chips
#254Disclaimer up front: I work for GM. I don't work on chips or components for my day job. What follows is solely my own opinion. Some things to emphasize: OEMs (GM, Ford, Toyota, VW, etc) do not design components, and they do not want to. They design specifications for components, and then get suppliers to bid. This is great for efficiency in established ecosystems, not great for agility. To my knowledge, GM did not ca…
> If you were going to design a new car electrical architecture from scratch today, you would have something like a 40-60V system with a centralized controller (or pair of controllers in a safety redundant configuration).
Aircrafts historically been using high frequency AC, on both sides of the iron curtain (as both sides were copying each other.)
Old analog instruments actually benefited from AC availability.
And when SMPS were big, and heavy, transformers were much more reliable, and smaller (and they are still are, depending on the frequency)
3 phase power was also giving some interesting cost cutting benefits at the time
Re: Why Carmakers Can’t Transition to Newer Chips
#255Earlier quoted context omitted.
Taking a long time doesn't mean you've done more useful work.
But a longer testing can find more bugs.
So can a shorter one.
(In a box at 120°C for a day is roughly equal to a thousand days at room temperature).
Smarter not longer. Write in a memory-safe language and you don't need to pay people to maintain spreadsheets of memory allocations...
Re: Why Carmakers Can’t Transition to Newer Chips
#256Earlier quoted context omitted.
> If you sit on someone’s shoulders and forget that they’re doing most of the work, you can be shocked all you want when they collapse out from under you but nobody on the ground is going to have any sympathy at all for you. Ajax Fasteners where a small manufacturer in the name of Division of Labour, and when they went into receivership, it took down Australia's entire car industry. Let me repeat - Australia no longe…
> Ajax Fasteners where a small manufacturer in the name of Division of Labour, and when they went into receivership, it took down Australia's entire car industry. Let me repeat - Australia no longer has a car industry. Holy crap: https://www.abc.net.au/worldtoday/content/2006/s1719988.htm You'd think the car companies could have just bought the manufacturing assets of the supplier if it was this critical (that's assu…
Holy crap indeed
... but the Australian car industry was nothing more than rent seeking anyway, so it was a good thing we stopped funding a non-utility.
Re: Why Carmakers Can’t Transition to Newer Chips
#257Earlier quoted context omitted.
>40-60V system What makes that voltage a better trade off?
Siblings covered why 12 V is annoying, let's talk about why 12 V was chosen in the first place. 6 and 12 V electric systems in vehicles came about because lead-acid batteries made sense in this application, and cetpar. a higher voltage lead-acid battery is overall costlier to manufacture, because it contains more individual cells. Another big thing is that there are many switches and relays in a car, and those often…
Plenty of older diesel road vehicles like Land Cruisers run 48V for everything. They've been that way since the 80s (maybe 70s).
Note: These were never sold in the North American Market, but they're extremely common in Australia, South Africa, etc.
Re: Why Carmakers Can’t Transition to Newer Chips
#258Disclaimer up front: I work for GM. I don't work on chips or components for my day job. What follows is solely my own opinion. Some things to emphasize: OEMs (GM, Ford, Toyota, VW, etc) do not design components, and they do not want to. They design specifications for components, and then get suppliers to bid. This is great for efficiency in established ecosystems, not great for agility. To my knowledge, GM did not ca…
I'm not in the car industry. But I spec mixed analog/digital parts and so see a lot of ads and press releases for automotive parts. I'm seeing increasing offerings of two pair Power over Ethernet controllers, cables, and connectors.
That makes me think that as companies retire legacy gas/diesel products they'll probably switch to an automotive PoE standard. Allows you to to power the window lift regulator, door locks, and read the switches off a single 20 gauge cable. Weld a fully assembled door assembly to the body and than plug in a single cable. What's not to like?
Re: Why Carmakers Can’t Transition to Newer Chips
#259Earlier quoted context omitted.
Another factor I haven't seen mentioned in the responses yet is safety to human bodies. You (or your kid) can stick a wet finger in a 12V DC charger socket in your car and not get an electric shock, including any of the exposed contacts under the hood, including the battery terminals. But once you're up to 40-60V, the risk of electric shock to humans is actually something that needs to be factored in.
What amperage are we talking about here? Discussions of electrical safety solely in terms of voltage is nonsense.
Amperage is set by the resistance of the human body. That's in the order of 2kOhm, so at 50V, you get a current of 25mA. That's in the zone where it becomes quite intense for you.
At 12V, we are just talking about 6mA, where you can feel the electricity but it should not be hurting too much.
Re: Why Carmakers Can’t Transition to Newer Chips
#260Earlier quoted context omitted.
This isn't really a fundamental problem. It just means using relays with contacts rated for higher voltages. It's probably the easiest part of the bom on a typical vehicle to move to a higher voltage range. I use 125VDC contact/coil rated relays all the time.
It is a fundamental problem (it's physics). The current rating for relays drops off sharply as the DC voltage increases; you might see 125 V DC rating, but the current will be a fraction of the nominal current at the rated AC voltage. If you're using an relay rated for up to 250 VAC/DC, then the breaking capacity with DC might be as low as 1 % compared to AC. Bad relay datasheets don't mention this at all, or maybe o…
Speaking of good relay datasheets, some will also show contact resistance vs current. I recall one which noted that for small signals the resistance was very low, but if higher current was applied, the contact coating would burn off and the resistance rises permanently.