Radiation Test for Raspberry PI Zero. We tested Raspberry PI Zero with Cobalt-60. Total Doze is 230 [gray].

1. ©SIProp Project, 2006-2017 1
Radiation Test –Raspberry Pi Zero-
Noritsuna Imamura
noritsuna@siprop.org

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Purpose
Testing Total Dose for Raspberry PI Zero
Target Devices
Raspberry PI Zero: Ver.1.2
MicroSD Card: TOSHIBA 8GB Class10(TOSHIBA
MSDAR40N08G)

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Regulation
Target Radiation Dose
ISS(International Space Station) Orbit
SSP 30512 Revision C from NASA
Heat Sink： 0.5[mm] Thickness of Aluminum Plate
8773[rad/year] = 87.73 [gray/year]
Mission Period: 2.6[year]
87.73[gray/year] * 2.6[year] = 228.10 [gray]
Testing Radiation Dose
Radioactivity: Cobalt-60
Distance of the Radioactivity: 80[cm]
Testing Date: 22/Mar/2017
Irradiation Time: 5[h]
46[ray/h] * 5[h] = 230 [gray]

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Calculation Tables
Table１．SSP 30512 Revision C Table2．Dose Rate

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Test Method
Phase No. Task
Before Test 1 Setup Raspberry PI Zero, Consumption Current
Logger, Power Supply.
2 Set Current Date on Raspberry PI Zero.
3 Run the Testing Application on Raspberry PI Zero.
During Test 4 Get CPU’s Temperature & Current Time in Every
Minute.
5 Create Current Time as File and Write Current
Temperature in this File.
6 Get & Save Current Consumption Current by Logger.

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Test Application 1/2
Check Targets & Reason
CPU
Raspberry PI Zero’s parts are a CPU & a voltage regulator only.
Clock
The clock shifts by a radioactive noise.
MicroSD Card
MicroSD Card has a micro computer.
NAND Flash is weak in radiation.

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Test Application 2/2
1. #!/usr/bin/python
2. #coding:utf-8
3. import os
4. import commands
5. import datetime
6. import locale
7. d = datetime.datetime.today()
8. temp = commands.getoutput("vcgencmd
measure_temp").split('=')
9. date_form_body=d.strftime("%Y-%m-
%d %H:%M:%S ")
10. s=date_form_body + temp[1] + 'n'
11. date_form_file=d.strftime("%Y-%m-
%d_%H:%M:%S")
12. filename=date_form_file + '.log'
13. f = open(filename,'a')
14. f.write(s)
15. f.close()
Operations
1. Get CPU’s
Temperature
2. Get Current Time
3. Create File by
Current Time
4. Write CPU’s
Temperature &
Current Time in this
File.
5. Close the File
6. Exit the Application
7. Run this Appli Every
Minute by cron

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Consumption Current Logger
Reason
Consumption current goes up by total dose
degradation.
Operation
Get & Save Current Consumption Current Every 30
seconds.

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Test Environment
Top: Upper-Surface Figure, Lower Left: Front
Figure, Lower Right: Rear Figure
Red Circle: Raspberry PI Zero
Blue Circle: Irradiation Point

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During Test
The value of radioisotope, and an inside situation

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Test Result: CPU Temperature
Check Point Check Target Result Success
/ Failure
Are the files made
for every minute?
MicroSD Card The files were created with
the error for 1 second
every minute.
Success
Were the files for 5
hours of test time
made?
Clock Just files existed.
(Last – First) timestamps =
0:02.
Success
Isn't there any
inaccurate
temperature data?
CPU Almost all the data was
25.0[C]. Occasional the
data is 24.5[C]-26.0 [C].
Success
By the above-mentioned test result, I judged
that Raspberry PI Zero passed this test.

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Test Result: Consumption Current
0
20
40
60
80
100
120
経過（分）
-37.0
-30.0
-23.0
-16.0
-9.0
-2.0
5.0
12.0
19.0
26.0
33.0
40.0
47.0
54.0
61.0
68.0
75.0
82.0
89.0
96.0
103.0
110.0
117.0
124.0
131.0
138.0
145.0
152.0
159.0
166.0
173.0
180.0
187.0
194.0
201.0
208.0
215.0
222.0
229.0
236.0
243.0
250.0
257.0
264.0
271.0
278.0
285.0
292.0
299.5
306.5
ConsumptionCurrent(mA)
Irradiation Time (min, 0=Start Time, 300=End Time)
By the above-mentioned test result, I judged
that Raspberry PI Zero passed this test.
But Consumption Current is increasing after
230min. It will be expected that radiation breaks
if it is longer time.

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Test Result: Conclusion
By these test results, I judged that Raspberry PI
Zero had radiation resistivity.
It will be expected that radiation breaks if it is longer
time.