Patent ID: 7538585
Filing Date: 2009-05-26
Classification: H03F,H03G,H03H

Abstract:
1. A transconductor, comprising: first and second transistors each having a first gate, a second gate, a source, and a drain, the first and the second gate of the first transistor being independently controlled, the first and the second gate of the second transistor being independently controlled, differential voltage input being supplied between the first gates, the sources being connected with each other, a first control voltage being commonly given to the second gates, and the drains being differential current output terminals; third and fourth transistors each having a first gate, a second gate, a source, and a drain, the first and the second gate of the third transistor being independently controlled, the first and the second gate of the fourth transistor being independently controlled, the differential voltage input being supplied between the first gates, the sources being connected with each other, a second control voltage that differs from the first control voltage being commonly given to the second gates, and each of the drains being connected with either of the drains of the first and the second transistors so that polarities from the differential voltage input to the differential current output terminals are opposite to each other; and a current source connected with both of the sources of the first and the second transistors and both of the sources of the third and the fourth transistors.