Virtual Field Programmable Gate Array Triple Modular Redundant Cell Design

摘要

Space systems are becoming increasingly dependent on field programmable gate arrays (FPGAs) and yet the higher gate-count devices are vulnerable to the space environment. To compensate for this effect, triple modular redundancy tools have been developed. Unfortunately these tools complicate the user's design and they cannot cope with the so-called single event functional interrupt (SEFI). In this report, a method referred to as the virtual FPGA has been developed to provide an alternative. It is based on the combination of three FPGAs and radiation-hardened support circuitry. The basic idea involves voting each of up to 512 user input/output pins on all three commercial FPGAs using a radiation-hardened voting circuit. A hardened microcontroller manages the configurations of each of the three FPGAs and monitors upset statistics. Advanced packaging is used to form a component that seems similar in form to the single FPGAs that the concept intends to replace.