Audio System Modeling and Simulation

ABSTRACT

This presentation extends the concepts developed in the companion presentation, “SPICE and Beyond with SystemVison: Audio Amplifier Example”. Here, in order to provide accurate dynamic loading effects for an audio amplifier, we first develop a model of a loudspeaker. This model includes an electro-mechanical voice-coil and a non-linear speaker cone with aerodynamic drag. This model is verified for both time- and frequency-response, and is shown to represent realistic loudspeaker behavior. Then we turn our attention to modeling an Audio IC, a Philips TDA7056A 3 Watt BTL (Bridge-Tied-Load) Mono Audio Output Amplifier. The modeling process demonstrates that even if SPICE models are not readily available from the manufacturer, a straightforward building-block modeling approach can yield practical, “data-sheet accurate” models that allow integrated system design verification to proceed. We show how SystemVision’s new Datasheet Curve Modeler (DCM) feature can be used to extract data directly from a graphical image, and then automatically generate an executable model of that behavior.