Measurement of Radiation Absorbed Dose Effects in SRAM-Based FPGAs

Abstract

As of now, SRAM-based FPGAs are mainly preferred in the non-safety applications of NPPs. If the susceptibility to radiation effects of SRAM-FPGAs improves further, then the reliability of the applications can be improved. This experimental study investigates the radiation absorbed dose effects in SRAM-based FPGAs. The irradiation experiments have been conducted by keeping the device in both the power-on and power-off states inside a gamma radiation chamber of Co-60 source. In some applications, the device is deployed in the radiation environments and remains in the power-off condition for substantial period. At the time of need, the device may not function properly as demanded by the system due to the cumulative dose effect on SRAM-based FPGA. So the study of irradiation experiments on SRAM-FPGAs in the power-off state has its significant importance the same as the power-on state. The power supply current variation and the functionality failure of the device are monitored in both cases. In the power-on test, the device is configured with particular functionality and the parameters are measured continuously, but in the power-off test, the performance variations of the device are captured after configuring the device at particular time intervals during the course of the experiment. Along with the power supply current variation, we used an indirect method of measuring the propagation delay based on ring oscillator implementation. The device has been irradiated up to a dose level of 2.5 Mrad in power-on test and up to 50 Mrad in the power-off test.

KEYWORDS:

• Gamma irradiation
• Nuclear power plant I&C systems
• Radiation effects
• SRAM-based FPGAs
• TID measurement
• Total ionization dose effects

Acknowledgment

The first author gratefully acknowledges the grant of the research fellowship from the Department of Atomic Energy, Government of India. The first author acknowledges the support of M. Sakthivel, Head, RTSD, IGCAR, H. Krishnan, RSD, IGCAR, Dr. Sunil Kumar, Head RSS/RDG, IGCAR and Dr. Puspalata Rajesh, WSCD, BARCF during the course of experiment.

Additional information

Funding

This work was supported by the Department of Atomic Energy, Government of India.

Notes on contributors

T. S. Nidhin

T S Nidhin is a senior research fellow at Real Time Systems Division of Indira Gandhi Centre for Atomic Research, Kalpakkam. He is working toward his PhD in Homi Bhabha National Institute. His research interests include FPGA-based digital system design, radiation effects in SRAM-based FPGAs and their mitigation techniques for reliable applications.

Anindya Bhattacharyya

Anindya Bhattacharyya is employed as a scientific officer-D at IGCAR, Kalpakkam. His current research interests include architectures for fault tolerant embedded systems, FPGA-based system design for high reliability applications, reliability and safety engineering and classical control systems. E-mail: [email protected]

Aditya Gour

Aditya Gour received his BTech in 2007 and MTech (Electronics) in 2011 from HBNI, Mumbai. He has been with IGCAR since 2007 and involved in designing various I&C for nuclear reactors and reprocessing facilities. His research interests include design of network-on-Chip (NoC), system on chip (SoC), condition monitoring system and high reliability embedded systems for reactor applications. E-mail: [email protected]

R. P. Behera

R P Behera is currently working as a scientific officer-F in Real Time Systems Division of IGCAR, Kalpakkam. He is involved in the design and development of safe and secure PLC system for nuclear instrumentation. His research interest includes high temperature, radiation tolerant, safe and secure electronics. E-mail: [email protected]

T. Jayanthi

T Jayanthi joined Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam in 1984, worked as a commissioning engineer in FBTR and various other projects in IGCAR. Presently, she functions as the head of Real Time Systems Division and is working on development and implementation of PFBR full scope operator training simulator and related research and development activities. E-mail: [email protected]

K. Velusamy

K Velusamy is working as an outstanding scientist and associate director of Nuclear Systems Analysis Group in the Indira Gandhi Centre for Atomic Research, Kalpakkam. His group is responsible for structural mechanics and thermal hydraulics design of Fast Breeder Reactor (FBR) components as well as reactor safety analysis. He is a senior professor in HBNI, Mumbai and under his guidance, 20 PhDs have been completed their thesis. He has 120 journal publications, 150 conference publications, 1 book and 925 citations to his credit. He is a fellow of Indian National Academy of Engineering. He was awarded DAE Scientific and Technical Excellence Award for 2006. He also received 9 DAE Group Achievement Awards. He was awarded HBNI Distinguished Faculty Award for 2015. He is a member of the Editorial Board of Annals of Nuclear Energy. He has been awarded the Certificate of Outstanding Reviewer from 5 Elsevier Journals. E-mail: [email protected]