An Exploration of Radiation Effects on Low-Node, High-Speed, Mixed-Signal Integrated Circuits

As circuits decrease in size and increase in speed, there will be a push to use higher performance electronics in the space sector, military sector, and the energy sector. As technology nodes decrease, they typically become more sensitive to radiation effects so extra design techniques must be utilized in order to make the circuits immune to radiation effects. Single Event Effects (SEEs) are a major concern as they will upset the transient response of the system. Total Ionizing Dose (TID) effects are also a concern as they will degrade the performance of the device until failure over a long period of time. Voltage Controlled Oscillators (VCOs) and Phase-Locked Loops (PLLs) are critical in serial communication systems and must perform in the 10s of Gigahertz (GHz) range. This thesis focused on implementing a varactor scheme in order to reduce the sensitive area of the varactors inside of the VCO and implementing Triple Modular Redundancy in the digital blocks for the PLL to make it immune the Single Event Effects. A SEE analysis was done on both the VCO and PLL to ensure radiation tolerance along with measuring the overall electrical characteristics. The radiation hardened VCO was found to have a nominal tuning range of 14GHz to 17.7GHz with a Phase Noise performance of -124dBc/Hz. The PLL was found to have a total peak to peak jitter performance at a Q of 7.5 of approximately 400fs with a rms jitter of 40fs and deterministic jitter equal to approximately 200fs. The total power consumption is 20mW for the PLL and a total area of 0.046mm^2