Methods and systems are provided for comparing currents. The method
includes driving a first current through a first X leg of a first current
conveyor circuit and a second current through a second X leg of a second
current conveyor circuit. The method further includes draining a third
current from a first X terminal of the first current conveyor circuit to
produce a first positive transistor current and a first negative
transistor current, and draining a fourth current from a second X
terminal of the second current conveyor circuit to produce a second
positive transistor current and a second negative transistor current. The
method further includes summing the first positive transistor current and
the second negative transistor current to produce a first current output,
the first negative transistor current and the second positive transistor
current to produce a second current output, and the first current output
and the second current output to produce a summed current output.