Fully symbolic analysis of large analog integrated circuits

Our fully symbolic analysis algorithms relax the circuit size limitation (due to exponential time and storage complexity) of previously known methods. Our implementation (AnalogSifter) will output simplified symbolic expressions in the desired frequency range for any desired transfer function, including input resistances, output resistances, as well as current and voltage gains. Symbolic pole and zero expressions were extracted accurately in the desired frequency range. Very compact symbolic expressions for the voltage gains of the two-stage CMOS and 741 operational amplifiers were obtained in less than 40 CPU seconds on a SUN SPARCstation 2, and the simplified results match well with the exact numerical values up to the unity gain frequencies in both the magnitude and phase versus frequency plots.<
>