Power transistors are used to control large electrical loads and are at the heart of the modern smart circuits used in all kinds of equipment from motor steering units to stereo amplifiers. More efficient transistors would thus contribute to the move toward greener power supplies by using energy sources in a more economical manner.
A power transistor is a type of tiny semiconductor valve that works behind the scenes to ensure the correct electrical current flows to devices. Two important power transistors on the market are known as DMOS (double-diffused metal oxide semiconductor) and LIGBT (lateral-insulated gate bipolar transistor).
Due to the lack of accurate models of how DMOS and LIGBT behave under different conditions -- such as temperature, high voltage and fast switching -- semiconductor manufacturers have tended to over-compensate in their design. This over-dimensioning of the power circuit chips to ensue a margin of safety has resulted in a costly waste of the materials used to make them and the energy they consume.
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