**4. Basic analysis of the search space**

This section presents a simple case study, a differential amplifier, to introduce and explain the usage of Simulated Annealing to automate the design of analog integrated circuit. Section 4.1 describes the features of the differential amplifier. Sec. 4.2 explains the modeling of the differential amplifier that allows its simulation and the usage of the SA. Finally, to improve the automation process, some optimization options on SA are applied and their results are discussed in Sec. 4.3 .
