Micro-opto-mechanical pressure sensors (MOMPS) based on integrated optical Mach-Zehnder interferometers (MZI) have been fabricated at IMEC, exhibiting much improved sensitivity and noise performance compared to their piezoelectric and capacitive counterparts. However, the design of next generation MOMPS systems on chip still remains uncertain due to the intrinsic multiphysics nature covering mechanical, optical and electrical phenomena. For this reason, we present a sophisticated, flexible and customizable algorithmic tool for the multiphysics simulation and design of highperformance MOMPS systems on chip, including mechanical and optical effects as well as the electronic circuitry for the readout. Furthermore, static and dynamic operating regimes are analyzed, also comparing analytical solutions with experimental results and demonstrating a good agreement. Finally, system noise contributions generated by the optoelectronic components and readout electronics are calculated and a static sensitivity of 8 mV/Pa is measured in the fabricated sensors.