An all enhancement PMOS op amp was designed and fabricated using the RIT standard PMOS process. The mask contained diagnostic components (resistors, discrete transistors and van der Pauw resistors), discrete stages of the op amp circuit, and a complete op amp circuit. Non-working op amp circuits were found due to parasitic loses. Circuit simulation using SPICE was performed. It was shown that inverter with~ the gain higher than 25 is not possible and the transistor load as a current source degraded the stage performances.
Doan, Hung Q.
"Evaluation of an Enhancement PMOS Operational Amplifier,"
Journal of the Microelectronic Engineering Conference: Vol. 4
, Article 13.
Available at: http://scholarworks.rit.edu/ritamec/vol4/iss1/13