Investigation and Analysis on Parasitic Parameters Of IGBTs for a PDP Driver IC

摘要

It is well known that the switching transient of an insulated gate bipolar transistor (IGBT) has multiple slopes and shows complex switching behavior. And along with that, modeling concepts for the nonlinear switching device-IGBTs have been proposed in circuit simulation. Several specific parasitic parameters and effects including nonlinear capacitances, current tail, gate resistor, stray inductances etc. have to be considered with priority since they dominate the static or dynamic characteristics. In the present work, emphasis is put on these nonlinear characteristics of IGBTs for a plasma display panel (PDP) scan driver integrated circuit. The situation that IGBTs turn on and turn off under a capacitive load is studies in detail through Saber using a physics-based IGBT model. The influences of crucial parasitic parameters to the driver circuit are revealed. In addition, that the driver circuit tends to oscillate during IGBTs turn-off and turn-on is also explained, which will increase switching loss and generates more EMI. It is of course unavoidable that a favorable tradeoff among some contradicting parameters requirement is necessary.