While plenty of empirical and physically descriptive RRAM models exist, their simulation run times become inconvenient for users when employed in large scale crossbar arrays. In this paper, we present a behavioral model of digital resistive switching devices, demonstrated on experimental PCRAM data which can see useful implementation in circuit analysis methods for compute-in-memory applications. This model is based on a pair of nonlinear ordinary differential equations that request switching time and threshold voltage inputs from the user, which are the most important parameters for system level design.