Patent ID: 6617923
Filing Date: 2003-09-09
Classification: H03F

Abstract:
A linear transconductance amplifier,wherein gates of a first and second transistors each having a grounded source are connected to each other and further connected to drains of said first and second transistors through resistors, respectively, and gates of a third and fourth transistors each having a grounded source are connected to the drains of said first and second transistors, respectively, thereby constituting an input terminal pair, the linear transconductance amplifier comprises means for forming an addition current by adding currents substantially equal to a half of drain currents of said third and fourth transistors, one differential output current is formed by subtracting the drain current of said third transistor from said addition current, and the other differential output current is formed by subtracting the drain current of said forth transistor from said addition current, and an input current applied to said input terminal pair is a differential current superimposed on a constant DC current.