Analysis of Dynamic Current Balancing in Multichip SiC Power Modules Based on Coupled Parasitic Network Model

The parasitic effect induced by the interconnections in device package brings about the dynamic current mismatch among paralleled dies, thus limiting the available capacity of power modules. In this paper, a general analysis based on coupled parasitic network model is carried out to reveal the mechanism of layout-dominated dynamic current balancing in multichip silicon carbide (SiC) power modules. First, according to the interrelation of parasitic parameters in the power module, a coupled parasitic network model at switching transients is established for the analysis of dynamic current balancing. For the validation of the proposed model, the parasitic parameters of two different module layouts considering magnetic coupling are extracted from Q3D. Based on the acquired parasitic parameters, the state space frequency-dependent model is reorganized to perform the electromagnetic coupling simulation in SIMPLORER. Finally, the simulation results and switching waveforms of SiC MOSFETs are combined to verify the effectiveness of the dynamic current balancing equations derived from the proposed model.