78xx mosfet
8) using MOSFET as a pass element is not straight forward, there is a fundamental differance in the way both devices work. a transistor is a current driven device and mosfet a voltage driven device. in case a N channel mosfet is used as a pass element a positive voltage(5 to 10 Volts depending upom type) is required with respect to the source, in which case a voltage multiplier or a voltage booster will be required, which will complicate the design of regulators.