Energy capability improvement of large DMOS transistors by adaptive current redistribution

Energy capability of DMOS transistors, e.g. in automotive applications, has become an important topic nowadays. This is because advanced technologies now allow significantly shrunken devices that reach their temperature limit already at low energy levels due to their smaller size. In this paper, a new adaptive technique by which the current densities inside the device are dynamically adjusted is proposed. It consists in dividing the DMOS into several (independently controllable) regions and using a feedback circuit which controls individual power densities according to temperatures measured by small sensors embedded in different regions of the device. The result is a more uniform temperature distribution across the active area which allows an energy capability improvement between 9.4% and 41%, depending on the operating conditions.