An Extension to VHDL-AMS for AMS Systems with Partial Differential Equations

This paper proposes VHDL-AMS syntax extensions that enable descriptions of AMS systems with partial differential equations. We named the extended language VHDL-AMSP. An important specific need for such extensions arises from the well known MEMS modelling difficulties where complex digital and analogue electronics interfaces with distributed mechanical systems. The new syntax allows descriptions of new VHDL-AMS objects, such as partial quantities, spatial coordinates and boundary conditions. Pending the development of a new standard, a suitable preprocessor has been developed to convert VHDL-AMSP into the existing VHDL-AMS 1076.1 standard automatically. The preprocessor allows development of models with partial differential equations using currently available simulators. As an example, a VHDL-AMSP description for the sensing element of a MEMS accelerometer is presented, converted to VHDLAMS 1076.1 and simulated in SystemVision.