An analog-design assistant tool and an example of its application

In this paper, we introduce an analog-design assistant tool (ADA), which was used to generate a database of 56,280 three-MOSFET circuit topologies. Having setup ADA to provide analog designers with amplifier topologies, it identified 5,103 three-MOSFET amplifiers based on the selection criteria given to the software. As an illustration of ADA capability of helping with circuit optimization, the transconductances of the transistors of each amplifier are automatically optimized by solving a nonlinear optimization problem that is set to maximize gains of circuits. In addition, ADA provides closed-form expressions of gain, input impedance, output impedance and reverse gain. To demonstrate that ADA can be used to identify and optimize new circuits, a previously unknown three-transistor amplifier with a high DC gain of ~40 dB was randomly chosen and fully designed in a 0.13-μm standard CMOS technology. The simulation results obtained with BSIM models show that the circuit topology provided by ADA is accurate and realizable. Using ADA will enable designers to save hours of time and provide them with range of circuits that are customized for their need.