Toward Generic Fully IntegratedGate Driver Power Supplies

An original method to power supply gate drivers has been previously developed. This solution takes advantage of power switch commutations to recharge periodically a storage capacitor, and then to create the necessary floating power supply, useful for many power electronic converters. It is a low cost solution that can be integrated, but it presents some disadvantages: the storage capacitor must be adjusted with respect to the ON state time duration, and a permanent ON state operation is forbidden. Moreover, with the existing solution, a low frequency operation is problematic, because a large storage capacitor would be required. The proposed work presents here an improvement of the solution, in order to a allow flexible or even permanent ON state time duration operation of a self powered metal oxide semiconductor field effect transistor, using few additional elements. This solution exhibits unexpected and fairly good efficiency levels and presents a high ability for a simple implementation and monolithic integration. Added to these new features, smaller values for the storage capacitor can be used for this self powered driver power supply, allowing from very low up to high frequency operation and high duty cycle operation. This particular solution may simplify the integration of the storage capacitor, in the same substrate as the main switch and its self powering circuits.