REGULATED CASCODE CIRCUIT AND AMPLIFIER HAVING THE SAME

摘要

A regulated cascode circuit and an amplifier having the same are provided to obtain a stable and high output resistor even at voltage below 1V without increasing an area. A regulated cascode circuit(30) includes first and second PMOS FETs(P-channel Metal Oxide Semiconductor Field Effect Transistor)(32,34) connected between a first terminal(31) and an output terminal(Vo) in series to receive a first power; first and second NMOS(N-channel Metal Oxide Semiconductor) FETs(36,38) connected between the output terminal and a second terminal(39) in series to receive a second power; and a regulation circuit(40) outputting a first control signal(CTRL1) for preventing the voltage change of a drain(X1) of the first PMOS FET, to a gate of the second PMOS FET on the basis of the drain voltage of the first PMOS FET and outputting a second control signal(CTRL2) for preventing the voltage change of a source(X2) of the first NMOS FET, to a gate of the second NMOS FET on the basis of the source voltage of the first NMOS FET.