Farewell 7805 & 7905

摘要

Linear voltage regulators of all shapes and sizes are used in countless electronic circuits. Classic devices such as the positive-output 7805 and the negative-output 7905 are indispensable in most designs, but they are not exactly champions in energy efficiency, due to their linear mode of operation. All superfluous power between the input and output pins of these regulators is simply converted into heat. Surely we can do better nowadays - more energy efficient and greener? That's what this article is about. The message is clear: down with power dissipation, up with switching!