Restabilizing Mechanisms after the Onset of Thermal Instability in Bipolar Transistors

The restabilizing mechanisms after the onset of thermal instability in bipolar transistors are studied by theoretical analyses, computer simulations and experimental measurements. Restability conditions are described by novel analytical formulae. Furthermore, the expression of collect current in the second fly-back point is given for the first time. The effects of emitter ballast resistance, collector-emitter voltage and thermal resistance on restabilization mechanisms are expressed and investigated.