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This article presents a radiation-hardened Cortex-R4F system-on-chip prototype with integrated total ionizing dose (TID) dynamic compensation capabilities, designed and fabricated in 28-nm fully depleted silicon-on-insulator (FD-SOI) technology. The processor was made robust to single-event effects, thanks to several design techniques: error correcting code (ECC) protected and bit-interleaved memories, optimized radiation-hardened sequential cells, and sensitive logic cells filtering. To counter the TID effects on the processor functionality and performances, the system embeds an integrated digital dosimeter. The dosimeter is capable of computing the TID in real time and providing the information to the system. Using a software lookup table (LUT), coupled with 28-nm FD-SOI technology support of asymmetric and wide-body-biasing, the reported TID can be converted to a request made to an external body-bias generator and be fully compensated. The system, operating at 0.9 V and 500 MHz, was tested under space grade radiations and has shown no failure in the 0 krad(Si) to 50 krad(Si) TID range. [ABSTRACT FROM AUTHOR]

This article presents a digital dosimeter for on-chip total ionizing dose (TID) computation, designed and fabricated in 28- and 22-nm fully depleted silicon-on-insulator (FD-SOI) technologies. FD-SOI has improved, by far, the robustness to single event effect (SEE), while TID may require fine control in high krad regime, leading to the interest for an integrated dynamic monitoring capability. The digital dosimeter is therefore implemented with a simplified TID hardware model and monitoring structure, capable of tracking and reporting TID value while being quasi-insensitive to voltage and temperature variations. The dosimeter is experimentally validated with gamma rays, showing less than 5% mismatch in dose estimate in the 0 to 50-krad(Si) range. Low-energy photons and alpha particles were used to extend the measurements to other sources and up to 500 krad(Si), where the mismatch with the theoretical estimate remains limited to 16%. The digital dosimeter, with an area of 0.002 mm2 and a very low imprint, is a suitable companion for any system requiring dynamic TID monitoring. [ABSTRACT FROM AUTHOR]