And what about a processor of Skylark L? I’m not so very well aware of rocket electronics, but interested in how it works, so I would be glad to find out your opinion. It’s supposed to be used in microgravity experiments and research. Does it increase the necessary power or not?
If you look at Wikipedia, it claims the product line has been:
RAD6000 → RAD750 → RAD5500
The Wikipedia pages have lists of notable spacecraft using the first two chips, but no such list for the RAD5500. A little bit of additional information:
-
RAD6000 is based on the CPU from the IBM RISC System/6000; it sounds like this is more or less a POWER1 or PowerPC 601
Lithography: 500 nm (0.5 μm) -
RAD750 is based on PowerPC 750
Lithography: 250 nm or 150 nm -
RAD5500 is based on PowerPC e5500,
Lithography: 45 nm SOI
At some point, the business was sold off from IBM and ended up as part of BAE Systems. You can see its product pages here,
wherein the Radiation-Hardened Electronics Product Guide lists a few properties of the RAD750 V2, RAD5545 SoC V1.1, & RAD5545 SoC V1.2 apparently being currently sold.
Notably, the RAD750 has, to my amateur understanding, 1/5 the error rate in some particular circumstance, slightly higher radiation tolerance, and is Qualified as “Q.V.” while the two RAD5500-series chips are merely “In-Progress”. The PDF is timestamped as created on 2020-09-22.
Its not about power its about durability. (Don’t use the word robust that’s a marketing term). A lower power processor will be more durable. It will last far longer. Less electronic stress in the components already in a stress environment.
Abstract concept seems to have written the beat explanation. Radiation hardened silicon is difficult and x86 simply wasn’t capable of it nor was CISC a good idea for apace flight st the time. RISC was making waves
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While this is off topic for the thread I feel the need that I really need to correct this statement you made and it’s principally because there is a concept of electromagnetic energy vs. High energy Mass particles… that’s being severely misrepresented here
Cosmic rays pass through even the earth my dude its not cosmic rays that are the problem its x-rays. Cosmic rays can cause bit errors but they don’t actually have the energy to do much if it all any damage …but x-rays definitely. Just a small difference here needing to be noted. The specific reason I’m actually noting it is because most people do get very confused when we refer to cosmic rays flipping bits in data on Earth. The reason cosmic rays has the potential to do this is because they are positive particles and they have intrinsic Mass. They are extremely high-energy and near the speed of light but they are not actually quanta of photons AKA light. So when these highly positively charged particles pass-through or stay or bounce off Electronics on Earth they take an electron and thus they flip the bit turning it from 1 to 0 most often. Now you might ask well how does it flip the bit the other direction that can happen when it pulls more than one electron because you have an alpha particle type cosmic ray but that’s also more rare than the simple type. So largely cosmic rays aren’t responsible for the phenomenon you’re talking about
However when select articles refer to a cosmic ray causing the damage there’s a very specific type called a HZE or High Z Energy Cosmic ray. These very selective and also rare cosmic rays (since most are simple protons or hydrogen nuclei)… these have the potential to do a lot of damage as they are much larger groups of protons and can definitely cause a dead pixel but the main source of damage again will always be X-rays and gamma rays. X-rays are light or electromagnetic radiation and thus have no intrinsic mass and don’t have the same properties that cosmic rays do and are able to energize Electronics circuits. That’s burning out your pixel in the sensor.
If you don’t believe me this is also the same reason they ask you to turn off your electronic devices when you pass them through the X-ray machine at the airport. 
. The power of that machine is so much lower so there is unlikely to be any damage however imagine something with the power of the Sun in terms of emission. You get the picture.
As for the ISS and its dead pixels. The reason it Encounters this is its proximity to the innermost Van Allen belt which should sit about 80 to 100 miles away at its closest distance. Unfortunately the Van Allen belt is not perfect and us you get X-ray radiation that leaks through it and there’s no atmosphere before that to stop it from bombarding the ISS. We are safely protected here on the ground because of nitrogen in the atmosphere which soaks up the last of most of the high energy EM that gets through earths magnetic field van Allen belts… The belts are a challenge to space flight as they at extremely high areas of radiation but that’s definitely a topic for when someone asks questions
Now you can all explain what really causes that damage to your friends and feel cool
I guess so this isn’t completely off topic I will relate it. So we all are familiar with the X-ray jacket full of lead that we wear when we take x rays? Well you’ll notice that almost all electronics that go into space or not RoHS compliant. Lead is still used due to unique properties. Also silicon that goes there has significant shield specifically designed to protect against the uniqueness of xrays. . It’s very expensive non-trivial stuff
Sauce: I’m literally a DOD engineer for space programs this is a nugget of basic knowledge since we spend a lot of time hardening stuff to deal with the very harash environment of space.
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I thought the ISS specifically tries to dodge around the Van Allen belts, and its radiation exposure is not as bad as deep space. Any idea how much shielding Mars provides in comparison?
I have definitely heard of the sort of photosensor deterioration that @FurryJackman is talking about on ISS, but I have not heard about similar issues on the long-lived rovers or Mars orbiters.
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farther away. Mars also has a weak magnetosphere … and a small think atmosphere. Enough to stop xrays (I made an overly detailed explanation above your post in reply to FJM) for the most part but UV is pretty bad. The lens already has stuff to deal with that so you get limited issues with the rovers. Honestly I feel we should send a few more probes and rovers out further. Some of saturns moons. A couple to Ceres and Eros. Only logical to start exploring further now that we are considering mars to become a base of OPs in the next few decades