Design criteria of CNTFET-based A/D circuits: a review

In this paper we review design criteria to evaluate the performance of typical analog and digital (A/D) circuits based on CNTFET, both in SPICE, using ABM library, and in Verilog-A, using a semi-empirical compact model for CNTFETs already proposed by us. The obtained results, with reference to a design of a phase shift oscillator, as example of analog circuit, are the same in static simulations and comparable in dynamic simulations. However using Verilog-A the simulation run time is much shorter and the software is much more concise and clear than schemes using ABM blocks in SPICE. Then we review a procedure in order to carry out static and dynamic analysis of basic digital circuits. In particular, to carry out the dynamic analysis, we consider both the quantum capacitance effects and the sub-threshold current. At last we analyze the timing performances of a NOT gate in order to define the optimal working conditions, emphasizing that the proposed method can be used to analyze the timing performance of any CNTFET-based logic gate.