Design, Simulation and Testing of MOSIS Fabricated CMOS Operational Amplifiers for Class Projects in an Analog I.C. Design Course

The paper describes use of MOSIS fabricated CMOS Operational Amplifiers as a real world design experience in senior level Analog Integrated Circuit Courses in Electrical Engineering. In the one-semester course on CMOS Analog I.C. Design offered at our department, design of a CMOS Operational Amplifier is required as a term project. Students are given a set of minimum specifications and are required to apply the learning they had into the design of a NMOS-input Operational Amplifier that can be implemented in an Nwell CMOS process. The specifications include open loop gain, gain-bandwidth product, phase margin, common-mode rejection range, slew rate and output swing on a specified load including capacitive loading. The requirements are (1) to create a Mathematica file of their design calculations, (2) verify the design with appropriate SPICE simulations, (3) create a layout design that passes all design rules, and (4) write a report and do a Powerpoint presentation to the class at the end. Projects that pass the design specifications and layout rules can be sent out to be fabricated. However, typical turn-around times do not allow the graduating class to have a chance to test and verify their design, and get the satisfaction and the real world experience of testing. By using MOSIS fabricated designs of previous generations, this missing link was completed.