Verify the Radiation Performance of TI MCU
TMS570LS3171 with Pencil Proton Beam
Scanning in the Proton and Radiation Therapy
Center of CGMH, Taiwan
Chih-hsun Lin, Shih-Chuan Yang, Kuo-Chang Han, Yi-Chun Tsai, Cheng-Ya Pan, Tsi-Chian Chao,
Chung-Chi Lee
Abstract-- In this paper, we present the result of TI MCU
TMS570LS3171 radiation test with scanning proton beam in the
proton and radiation therapy center of Chang Gung Memorial
Hospital (CGMH). CGMH is the first proton therapy center in
Taiwan. It is also open for proton radiation validations and tests.
The latest proton beam delivery technology, pencil beam
scanning (PBS), is also available. In this test, the proton beam
energy is 200 MeV. The total delivered fluence is 1.425x1011
proton/cm2 with 25 deliveries. No single-event latch up event is
observed. There are ten errors observed. Four of them are
internal memory errors. Six test program crashes are reported
and can be recover by power cycling.
I.
1. PROTON BEAM TEST FACILITY
T
HE
proton and radiation therapy center of Chang Gung
Memorial Hospital (CGMH) [1] is the first proton
therapy center in Taiwan. Its cyclotron for proton acceleration
and beam delivery system were designed and manufactured
by Sumitomo heavy industries, Ltd. The construction of
proton and radiation therapy center of CGMH was started in
2011. The first proton beam delivered to a treatment room
was in 2013. In December 2014, a trial of six patient trials
was completed. The official opening of proton and radiation
Manuscript received August 10, 2007.
C.H. Lin is with Institute of Physics, Academia Sinica, Taipei, Taiwan
(telephone: 886-2-2789-6787, e-mail: chihhsun.lin@phys.sinica.edu.tw).
S. C. Yang is with System Development Center, National Chung Shan
Institute of Science and Technology, Taoyuan, Taiwan (e-mail: koelisu@hotmail.com).
K. C. Han is with System Development Center, National Chung Shan
Institute of Science and Technology, Taoyuan, Taiwan (e-mail:
hank@ncsist.org.tw).
Y.C. Tsai is with Particle Physics and Irradiation Core Laboratory,
Institute for Radiological Research, Chang Gung University / Chang Gung
Memorial Hospital, Taoyuan, Taiwan (e-mail: momoco.1101@gmail.com).
C.Y. Pan is with Medical Physics Research Center and Institute for
Radiological Research, Chang Gung University / Chang Gung Memorial
Hospital, Taoyuan, Taiwan (e-mail: cypan@mail.cgu.edu.tw).
T.C. Chao is with Department of Medical Imaging and Radiological
Sciences, Chang Gung University, Taoyuan, Taiwan (e-mail:
chaot@mail.cgu.edu.tw).
C.C. Lee is with Department of Medical Imaging and Radiological
Sciences, Chang Gung University, Taoyuan, Taiwan (e-mail:
cclee@mail.cgu.edu.tw).
978-1-5386-8263-0/18/$31.00©2018 IEEE
therapy center of CGMH was in November 2015. Important
parameters of the proton and radiation therapy center of
CGMH are given in Table 1.
There are four treatment rooms and an experiment hall in
the proton and radiation therapy center of CGMH. The proton
beam of first and second treatment rooms are delivered as the
broad field up to 25 cm x 25 cm by using the wobbling
technology. The third and fourth treat rooms are equipped
with the latest proton beam delivery technology, pencil beam
scanning (PBS). With such technology, the proton beam is
delivered with a small spot size and scans through the target
area to create a designed dose distribution by adjusting
scanning speed and proton beam amplitude. The scanning
speed of proton beam in the proton and radiation therapy
center of CGMH is up to 20 m/sec.
TABLE I
PARAMETERS OF THE PROTON AND RADIATION THERAPY CENTER, CGMH.
Parameter
Beam Energy
Beam Current
Treatment Room
Experiment Hall
Value
70 MeV – 230 MeV
Up to 300 nA at 230 MeV
Four with gantries
One with fixed beam port
The fifth room is an experiment hall dedicated for proton
and neutron related experiments. The field size of broad beam
in the fifth room is produced by using a passive beam system,
double scatters with a downstream modulator. The maximum
field size is 6 cm x 6 cm with uniformity < 10%. A quasimonoenergetic neutron beam is generated by injecting proton
beam with energy 230 MeV into Lithium-7 targets with
selectable thickness. The fifth room is under construction and
will be ready for experiments in late 2018.
II. TEST SETUP AND METHOD
The device under test (DUT) is TMS570LS3137 [2]. It is a
high-performance automotive-grade microcontroller for
safety-critical applications. The embedded CPU core is ARM
Cortex-R4F 32bit RISC CPU with integrated memories and
multiple communication interfaces. The evaluation kit of
TMS570LS3137 was used directly in this proton irradiation
test as shown in Fig. 1. A set of test programs with following
functions were running and reporting errors continuously
during irradiation:
 Built-in programs, STC (Self-Test Control) and PBIST
(Programmable Built-In Self-Test), are used to verify
CPU functions and internal memories.
 Two CAN interfaces of TMS570LS3137 are connected
together to perform a loopback test. A test program
continues sending and receiving status packets via these
two CAN interfaces. Each bit of received CAN packets
is verified.
 A UART transmission program transmits a 14 bytes
packet with test results continuously. It is also a
validation of UART interface.
 An Ethernet transmission program with TCP/IP
protocols transmits the same packet continuously as the
UART transmission program. It verifies the Ethernet
interface.
to display results with the Ethernet connection to the control
PC.
Fig. 2. Block diagram of TMS570LS3137 irradiation tests.
Fig. 3. Test setup of TMS570LS3137 irradiation tests.
III.
Fig. 1. Evaluation kit of TMS570LS3137. The size of TMS570LS3137 is
1.6 cm x 1.6 cm.
It takes less than one second to run through all test
programs once. The block diagram of TMS570LS3137
irradiation test setup is shown in Fig. 2. Fig.3 shows the test
setup. The evaluation kit of TMS570LS3137 was placed
above the solid phantom on the couch. The proton beam was
delivered from top. The solid phantom was used to stop
proton beams. A laboratory power supply provided 12 Volt
power to the evaluation kit of TMS570LS3137. An Agilent
34410A multimeter was connected in serial to measure its
current for the detection of single event latch up. The control
PC was connected to the evaluation kit to receive status
packets via RS232 and Ethernet links. The remote PC is used
3. PROTON BEAM CONDITION
The 3rd treatment room with scanning beam is used for this
test. Proton beam parameters used in this test are listed in
Table 2.
TABLE II
PARAMETERS OF PROTON BEAM USED IN THIS TEST.
Parameter
Beam Energy
Scanning Area
Scanning Time
Scanning Fraction
Scanning Speed
Proton Flux
Value
200 MeV
2.5 x 2.5 cm2
30 seconds per scan
20 per scan
0.2 m/sec
1.9 x 108 /cm
The scanning time is chosen to be 30 seconds, which is
much longer than the execution time of all test programs (< 1
second). Fig. 4 shows the estimated proton fluence
distribution of one scan, projected in X and Y directions, by
using real beam profiles. The uniformity of fluence
distribution is better than 10% in the area of 2.0 x 2.0 cm2.
The σ of proton beam energy distribution is about 0.79 MeV
according to the simulation. The time of beam on, beam off
and error detection is recorded in second in order to calculate
the total irradiated fluence precisely.
V. SUMMARY
TI MCU TMS570LS3171 has been irradiated with
scanning proton beam in the proton and radiation therapy
center of Chang Gung Memorial Hospital (CGMH). The total
irradiated proton fluence is 1.425x1011/cm2. There are six test
program crashes and four memory errors detected. There was
not an event of single-event latch up observed.
VI. REFERENCES
[1]
[2]
Fig. 4. Estimated proton fluence distribution of one scan, projected in X
and Y directions
IV. TEST RESULTS
In this irradiation test, twenty-five scans were performed in
total with the accumulated proton fluence 1.425x1011/cm2.
The typical current of 12V power line ranges from 0.15 A to
0.19 A. There was not an event of single-event latch up
observed. Six program crashes (functional interrupts) were
detected by observing stable current at 0.16 A or 0.1 A and
no UART outputs. The evaluation kit of TMS570LS3137 was
recovered successfully by power cycling in all program
crashes. Four errors of CPU RAM check were reported in
different scans. All of them were recovered in the next
execution of test program.
Proton and Radiation Therapy Center, Linkou Chang Gung Memorial
Hospital, https://www1.cgmh.org.tw/intr/intr2/c33e0/english
Texas Instruments, TMS570LS3137, 16/32 Bit RISC Flash MCU, Arm
Cortex-R4F, http://www.ti.com/product/TMS570LS3137