1. An apparatus for designing a transformer in an integrated circuit, the apparatus comprising: a processor; a user interface adapted to allow a user to input one or more desired characteristics of the transformer; wherein the one or more desired characteristics include load impedances at primary and secondary coils of the transformer; wherein the processor is configured to determine sufficient optimal characteristics of the transformer to define the transformer for fabrication in the integrated circuit by performing the steps of: combining the one or more desired characteristics with other preset characteristics of the transformer or the integrated circuit, generating a first model of the transformer with typical load impedances, simulating the first model having the combined characteristics to determine performance, processing results of the simulation to calculate performance with the load impedances specified by the user, further processing the results to generate a mathematical model that includes tuning capacitors coupled to primary or secondary coils of the transformer to achieve a tuned LC circuit with the inductance of the transformer coils, drawing on a rule-set of one or more rules relating to general dependency of at least one design criterion on another design criterion, the design criteria relating to one or more of physical, geometrical or performance characteristics to enable modification of the first model, and iteratively determining a design solution for the transformer through one or more simulations and modifications using the rule-set, wherein the user interface is adapted to allow a user to input one or more optimization targets, and wherein the processor further performs the steps of: solving a constrained optimization problem to determine optimal values of the tuning capacitors based on the one or more desired characteristics and the one or more optimization targets.