And if you are curious about the modern radiation hardened CPUs then the current state of the art ones are the MOOG BRE440 [0] and the BAE RAD5500 [1], 5545 [2] being the highest performance multi core one.
Even more interesting that they both use the IBM POWER architecture!
There have been a number of rad-hard SPARC chips from different vendors tthat have flown along the way, and I know Frontgrade/Gaisler currently sells a SPARC v8 version, which isn't that far behind the 'state of the art' as the e5500 based PPCs from BEA (at least as far as state of the art in space rated, rad-hard processors goes...it's a conservative market). Quite a few rad-hard ARMs out there farther down the performance curve.
Frontgrade also advertises a rad-hard RISC-V, as does Microchip (a PIC64 variant), that I know nothing about, but seems like an inevitable next step. Seems like you could grab some Xilinx rad-hard FPGA and bobs your uncle.
NooneAtAll3 2 minutes ago [-]
what scale of radiation do such hardened designs target?
fred_is_fred 20 minutes ago [-]
Wow, until you posted this I thought Moog was just a synthesizer company. And a bit of an odd one at that based on how I saw that synth presented.
wbl 5 minutes ago [-]
Cousins. One made synths the other flight controls.
kjs3 49 minutes ago [-]
Interesting combination of 'remarkable' and 'wtf' that we fling nuclear weapons around with the computational equivalent of a couple of TRS-80s[1]. I can only imagine the sighs of relief from the devs when things like the MIL-STD-1750a and later rad-hard SPARC and PPC variants came along.
[1] yes...I know the TRS-80 had a z80, not an 8085. Close enough.
Arodex 27 minutes ago [-]
You don't need much calculation power to manage a 30-min ballistic trajectory.
The inertial navigation system is the very crazy part, along with the nuclear fusion warhead design itself.
Excellent find. And yes, obviously this is slop. 106 rad is exactly nothing for nuclear usage.
ralferoo 9 minutes ago [-]
Bad typesetting just indicates poor editing, not slop IMHO.
I guessed after about a second of thought that this actually meant 10^6. If I had to guess how this happened, somebody just wrote their prose in Word with the 6 in superscript and cut and paste it into HTML which lost the formatting.
grosswait 1 hours ago [-]
Very interesting! Definitely some jargon I’ve not come across before.
“The chips were made on a n-on-n+ epitaxial substrate to provide latchup control, extensive guard rings around transistors were used and hardened oxides”
egorfine 45 minutes ago [-]
> Galileo space probe [..] How many IC’s were needed? Over 50,000 for the probe itself, backups, testing chips etc.
I seriously doubt you need to fabricate 50k CPUs for a single space probe, including backups, testing chips, etc.
Zenst 42 minutes ago [-]
That number was probably shaped by minimum production-run requirements, alongside the need for software development units, along with other factors, like the use in Trident II and other quests we may not know about.
api 33 minutes ago [-]
> other quests we may not know about.
Back then an interface between terrestrial computer systems and a Zeta Reticulan spacecraft required a small supercomputer on our side.
Rendered at 13:23:17 GMT+0000 (Coordinated Universal Time) with Vercel.
Even more interesting that they both use the IBM POWER architecture!
0, https://www.moog.com/products/avionics/spacecraft-avionics/b...
1, https://en.wikipedia.org/wiki/RAD5500
2, https://web.archive.org/web/20190226111129/https://www.baesy...
Frontgrade also advertises a rad-hard RISC-V, as does Microchip (a PIC64 variant), that I know nothing about, but seems like an inevitable next step. Seems like you could grab some Xilinx rad-hard FPGA and bobs your uncle.
[1] yes...I know the TRS-80 had a z80, not an 8085. Close enough.
The inertial navigation system is the very crazy part, along with the nuclear fusion warhead design itself.
https://youtu.be/AazmxNs5kmE?is=2LE2q3rBSWDyTs7j
> An 8085 processor that could handle 1×106 rads of radiation with only a 25% reduction in performance, and 3×106 rads with a 40% drop.
Hmm, from where did they copy-paste this mangled scientific notation?
Ah here we are, pg. 37 (46 in PDF file): https://apps.dtic.mil/sti/tr/pdf/ADA063902.pdf
I guessed after about a second of thought that this actually meant 10^6. If I had to guess how this happened, somebody just wrote their prose in Word with the 6 in superscript and cut and paste it into HTML which lost the formatting.
“The chips were made on a n-on-n+ epitaxial substrate to provide latchup control, extensive guard rings around transistors were used and hardened oxides”
I seriously doubt you need to fabricate 50k CPUs for a single space probe, including backups, testing chips, etc.
Back then an interface between terrestrial computer systems and a Zeta Reticulan spacecraft required a small supercomputer on our side.