Thevenin forms of digital discrete-time non-Foster RC and RL circuits

Previous design approaches for digital discrete-time non-Foster circuits have typically employed ideal current-output digital-to-analog converters to establish port currents based on measured voltages. In this paper, the design of digital discrete-time non-Foster circuits is presented for the case of voltage-output digital-to-analog converters with finite source impedance. These finite-impedance converters act as Thevenin sources that can be converted to Norton-equivalent sources for design and analysis. However, it is also straightforward to incorporate the finite source impedance directly into the signal processing, and this is the approach presented. In addition, it is often desirable to add series resistance to improve stability or to mitigate parasitic resistance, so the design of series resistor-capacitor and series resistor-inductor digital discrete-time non-Foster circuits are considered. Finally, unavoidable time-delay latencies associated with conversion time and computation time are also included.