We extend a class of analog CMOS circuits that can be used to perform many analog
computational tasks. The circuits utilize MOSFET's in their subthreshold region
as well as capacitors and switches to produce the computations. We show a few
basic current-mode building blocks that perform squaring, square root, and multiplication/division
which should be sufficient to gain understanding of how to implement other power
law circuits. We then combine the circuit building blocks into a more complicated
circuit that normalizes a current by the square root of the sum of the squares
(vector sum) of the currents. Each of these circuits have switches at the inputs
of their floating gates which are used to dynamically set and restore the charges
at the floating gates to proceed with the computation.
