Figure 2.

(A) Visualization of the 3 dB-thresholds on which the signal compatibility analysis is based. i₀, i₁ represent the output values at the upper and lower threshold respectively, and j₁, j₀ the corresponding input values. (B) Compatibility of gates in Cello’s library. For each pair of source gates, the number of compatible target gates is presented. Interestingly, there is a significant number of pairs not compatible with any subsequent NOR gate. This limits the number of gates available for assignment at a distinct position within the circuit.