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Radiation considerations for electronic design --- books?


Richard Henry

Jan 1, 1970
Ancient_Hacker said:
You have to watch out for specmanship with these statistics.

The average space environment isnt too bad, but there are occasional
"cosmic rays" with really high energies, some higher than can be
simulated on Earth. IIRC there was one cosmic ray measured at enough
energy to have moved a baseball!

So a stat of say 10% leakage degradation at 1000 Rads over 1000 hours
isnt terribly meaningful. That number doesnt tell you anything about
what happens when one 800MeV particle hits your 74HC04.

It's like saying nobody is affected by traffic accidents as the average
person gets hit by 0.00003 of a car per year.

You have to design in error-detection and correction circuitry if you
want the electronics to survive a serious cosmic ray.

Or surround your electronics with baseballs.

Jim Thompson

Jan 1, 1970
Well, the first MOS anyone could talk about, maybe.

They were forbidden until the "big blow". Then I was put on the team
to completely review all systems. I discovered that the power
supplies were so redundant that one failing took all the others with
it. We had to get hexfets space-qualified to expeditiously solve the
problem... a full-blown redesign would have taken forever.

...Jim Thompson

Michael A. Terrell

Jan 1, 1970
martin said:
"Vacuum leak testing for the Royal Canadian Mounted Police;"

I dare not ask......


It probably has something to do with protecting the Mounties from the
"Homer Simpson" character on the sci.electronics.* newsgroups.

Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida


Jan 1, 1970
Isn't MOS banned for space apps due to possible contamination? I know
cadmium is because it corrodes titanium.

MOS and CMOS in particular are quite common in space applications. The old
RCA 1802 uP was manufactured in rad hard versions specifically for space


Jan 1, 1970
Spehro said:
Hi, all:-

would appreciate recommendations for books on designing electronics to
live in relatively high radiation space environments (not quite
rad-hard). Particularly power MOS circuits and digital.

Thanks in advance..

Best regards,
Spehro Pefhany

Back in the dark ages, circa mid 1960's, there was a program similar to
SPICE called SEPTRE that was all about solid state electronics radiation
modeling. I think it ran on Univac 1107 and 1108 mainframes. I wonder if
anybody has a current equivalent.

Jeroen Belleman

Jan 1, 1970
Spehro said:
Hi, all:-

would appreciate recommendations for books on designing electronics to
live in relatively high radiation space environments (not quite
rad-hard). Particularly power MOS circuits and digital.

I don't know about books, but here are some hints. Radiation damage
in bipolar transistors results in a reduction of Hfe, initially at
low collector currents (<100 uA). Hfe decay as a function of dose
is apparently exponential, with a decay constant of about 700 Gy
for small-signal transistors like the 2n2222 for example.

FETs suffer a threshold voltage change. I have no quantitative
data on hand.

The obvious message in discrete designs is to allow for large
changes in these parameters.

In integrated circuits, you have no control over these things.
Old chips, with only NPN transistors, are fairly resistant, and
continue to function, more or less, up to several kGy. Watch out
for devices with lateral PNP transistors, like, say, an LM337
regulator. That one dies with less than 30 Gy. Modern fast TTL
logic likewise dies from a few tens of Grays, whereas old-fashioned
LS or S series survive kGy doses with ease. ECL, at least the
old Motorola 10k and 100k families, is very good, surviving to
10 kGy and beyond. I have no data for the newer series yet.

A whole other subject is Single Event Upsets, where a FF in a
logic circuit may get flipped by a passing particle. There are
design methods based on redundancy and voting that make logic
more robust. I have no experience in the matter. I tend to keep
logic subjected to radiation very simple, and rewrite the whole
register space repetitively from a remote location, so that any
SEU errors get wiped out every second or so.

There are a few web sites that contain some information about
radiation effects in electronics:

The ESA radiation effects website:

JPL/NASA used to have something similar, but the link I have,, is dead. Maybe you can
find it again, if it still exists somewhere.

Slides from a course about radiation effects in semiconductors,
given here at CERN by Martin Dentan in April 2000:

The web pages from the radiation working group here. Not sure
if these are accessible from outside CERN. Anyway, here it is:

Hope that helps a bit.

Jeroen Belleman