line 82 is active an amplified ineg electrical current flows from the current mirrors 61 through the output node 92 through the resistor r and back through the output node 90 to the current mirrors 62 fig4 a and 4b illustrate the ipos and the ineg electrical currents respectively on the signal lines 80 and 82 for an example synthesized waveform the ipos and the ineg electrical currents flow in the same direction at the signal lines 80 and 82 fig4 c illustrates the resulting amplified electrical current flow through the resistor r the output voltage across the resistor r provides the synthesized analog waveform transmitted over the transmission line 70 referring again to fig3 the dynamic current mirror circuit 26 also includes a set of transconductance amplifiers 50 53 each of the transconductance amplifiers 50 53 senses a common mode voltage vc at a node 75 the transconductance amplifiers 50 and 51 implement a negative transconductance factor g m and the transconductance amplifiers 52 and 53 implement a positive transconductance factor g m if the common mode voltage vc at the node 75 increases then the current from the amplifiers 52 and 53 each increase and the current from the amplifiers 50 and 51 each decrease thereby decreasing the common mode voltage vc if the common mode voltage vc decreases then the current from the amplifiers 52 and 53 decrease while the current from the amplifiers 50 and 51 increase which causes an increase in the common mode voltage vc taken together the current sources 50 53 improve output linearity of the dynamic current mirror circuit 26 and decrease the common mode output voltage vc at the node 75 fig5 provides detailed schematics of one embodiment.