Single / multiple bit flip events in industry computers (PLCs)
Industry computers are used for automated control for critical and not critical application. Since many applications request 24/7 hours performers for many years without any power reset. The soft errors cause be terrestrial radiation must be taken to the count during FW and HW development.
Our investigation covers the radiation testing with neutrons (37MeV) under particle accelerator. We are testing and validating soft error rates provided by vendor and future more we are implementing FW features to increase radiation robustness against soft errors. Our focus are SRAMs, Siemens ASICs and flashes. We are testing SIMATIC PLC with radiation dose which are approximately in range of 500 – 10 000 years of terrestrial radiation in one hour beam time. The testing is provided in distance 2-5m from particle accelerator with many samples (up to 20) for better statistical certainty. We developed our own “Golden samples” for better measurement comparation between tests and particle accelerator (according JEDES89B).
The particle accelerator in nuclear laboratory at Řež, Czech Republic has very wide range of provide neutron beam intensity. One of the key aspects of this beam is his beam width. This allows us to test many samples not in line but next each other. Our typical irradiation area is 50cm x 50cm.
Additionally, we develop our own method how to simulate single / multi bit error in not radiation environment by applying high level of electromagnetic disturbance directly or SRAM chip.