Analog and Digital Behavioral Modeling
Laplace sources let you describe the S-plane linear transfer function of a circuit block. Function sources let you model nonlinear behavior. The source can be a mathematical function of any other circuit variable, such as a node voltage or a device current. Z transform sources let you handle Z transform expressions as, for example, in digital filters. Expressions can also be used for resistor, capacitor, and inductor values. Here are some samples: G*b0/(s**2+b1*s+b0): low pass filter exp(-c*s*(r+s*l)**.5): transmission line -k*(v(p)-v(c)+u*(v(g)-v(c)))**1.5: a triode VZ+tempco*(TEMP-27): reference voltage source Sin(2*pi*T)*Exp(-T): damped sine wave source Powerful digital behavioral primitives include logic expressions, pin delay blocks, and constraint checkers. These allow modeling of complex commercial parts like adders, multipliers, converters, and arithmetic logic units.