ABSTRACT
This chapter presents linear dependent sources that can be used to develop simple models of active elements such as amplifiers and transistors. It discusses nonlinear dependent sources. These sources can be used to model circuit operations such as “summers” and “multipliers” in block-diagram format. Active devices can only be modelled by the use of “dependent sources”. Unlike the independent sources, dependent sources have their output controlled by a number of inputs. PSpice has four dependent (controlled) sources: voltage-controlled voltage source, voltage-controlled current source, current-controlled current source, and current-controlled voltage source. Each of these dependent sources is recognised by PSpice as a component starting with the letter E, G, F, and H, respectively. The controlled sources have been linearly dependent on the controlling inputs. PSpice allows the user to specify polynomial (nonlinear) dependent sources in which the controlling inputs can be described in the form of a polynomial.
