High-Efficiency and Fully Integrated Self-Powering Technique for Intelligent Switch-Based Flyback Converters

To answer the low cost and simplicity necessities for massive market converter applications (home appliance and automotive, for example) and with the help of the monolithic integration, new components have been developed by industry. This approach leads to cost and volume reductions. In the case of intelligent power MOSFETs, the control part is supplied through one supplementary winding, integrated with the flyback converter´s inductor. The result is an extra cost and a specific design of passive devices. We propose an original solution to allow permanent and wide-range operations, with no need of any supplementary third coil to power supply the intelligent switch. This solution can be easily integrated in the same substrate within the power switch without special needs for insulation, bringing fairly good results in flyback converter applications based on the use of intelligent switches. In addition, the powering technique is used to clamp the turn-off overvoltage. The global converter´s operation takes advantage of the implementation of this new technique.