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Lockheed Martin was responsible for the construction of Juno. But I was wondering who built the chips Juno uses for its onboard computers, and whether or not they are radiation hardened. I would assume that, in addition to being in the vault, they are hardened. Does anybody know where Lockheed got the chips themselves?

Phiteros
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  • I suspect they use industrial grade, general usable microcontrollers. Considering the Lockheeds strong contact with the U.S. military they were produced by U.S. companies, despite that the chinese/south korean versions had been cheaper. On the software side, somewhere I've heard they use wxworks, but it is not a really uptodate info. – peterh Jul 07 '16 at 15:54
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    There likely is multiple suppliers. Each instrument will have it's own chips, which are likely different than others. Also, this kind of information isn't generally public domain. – PearsonArtPhoto Jul 07 '16 at 15:58
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    @PearsonArtPhoto Yes, I'm fairly certain this information is proprietary. – called2voyage Jul 07 '16 at 16:06
  • @PearsonArtPhoto That explains why I haven't been able to find any information about it on the web. I'd think that the suppliers would at least be known. – Phiteros Jul 07 '16 at 16:31
  • @Phiteros Don't give up just yet. You got one answer, so you may at least get some partial information. – called2voyage Jul 07 '16 at 16:32
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    @peterh: no. Just about every spacecraft uses space-grade radiation-hardened components which have much more rigorous specs than industrial components. – Hobbes Jul 07 '16 at 16:41
  • Especially NASA/ Millitary ones, that tend to spend top dollar. – PearsonArtPhoto Jul 07 '16 at 21:59
  • @PearsonArtPhoto -- Not SpaceX. They are using commercial off the shelf (COTS) computers,but in large numbers. Single event upsets are not a problem. A rogue / malfunctioning computer is detected, restarted, and brought back in line. This results in a huge advantage in terms of vastly reduced cost and vastly increased computing power compared to rad-hardened computers that not so reminiscently bring one back to the previous millennium. However, this SpaceX concept might not work in a setting as hostile as Jupiter. – David Hammen Jul 07 '16 at 23:28
  • BTW, the given answer is 100% correct. Juno uses a RAD750 manufactured by BAE systems (actually a pair of them, for redundancy). It has the computing power of a 1999 personal computer, but with limited memory compared to a 1999 personal computer, and even more limited storage compared to a 1999 personal computer. Given Jupiter's extremely hostile environment, and given the time frame in which Juno's avionics were established, I doubt there was a better solution. – David Hammen Jul 07 '16 at 23:28
  • SpaceX uses rockets and stuff in LEO. I suspect the Red Dragon will use at least some rad hardened parts. – PearsonArtPhoto Jul 07 '16 at 23:30
  • @DavidHammen ...and yet the accelerometer chip is secret! :-) – uhoh Jul 08 '16 at 10:10

1 Answers1

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BAE Systems is one supplier for the command and data handling processor.

https://en.wikipedia.org/wiki/RAD750

The RAD750 is a radiation-hardened single board computer manufactured by BAE Systems Electronics, Intelligence & Support.[1] The successor of the RAD6000, the RAD750 is for use in high radiation environments experienced on board satellites and spacecraft.[2] The RAD750 was released in 2001, with the first units launched into space in 2005.[1][3]

The CPU has 10.4 million transistors, nearly an order of magnitude more than the RAD6000 (which had 1.1 million).[3] It is manufactured using either 250 or 150 nm photolithography and has a die area of 130 mm2.[1] It has a core clock of 110 to 200 MHz and can process at 266 MIPS or more.[1] The CPU can include an extended L2 cache to improve performance.[3] The CPU itself can withstand 200,000 to 1,000,000 rads (2,000 to 10,000 gray), temperature ranges between –55 °C and 125 °C and requires 5 watts of power.[1][3] The standard RAD750 single-board system (CPU and motherboard) can withstand 100,000 rads (1,000 gray), temperature ranges between –55 °C and 70 °C and requires 10 watts of power.[3]

The RAD750 system has a price that is comparable to the RAD6000 which is US$200,000 per board (per 2002 reference).[4] However customer program requirements and quantities will greatly affect the final unit costs.

The RAD750 is based on the PowerPC 750.[1] Its packaging and logic functions are completely compatible with the PowerPC 7xx family.[3]

http://www.jpl.nasa.gov/news/press_kits/JunoLaunch.pdf, page 15:

Command and Data Handling

Command and data handling includes a RAD750 flight processor with 256 megabytes of flash memory and 128 megabytes of DRAM local memory. It provides 100 Mbps total instrument throughput, more than enough for payload requirements.

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