Algorithmic analogue-to-quaternary convertor circuit using current-mode CMOS

A new current-mode CMOS algorithmic analogue-to-quaternary data convertor circuit has been realised in a standard polysilicon-gate CMOS technology. This circuit accepts an analogue current input and develops a set of quaternary, base-four, output currents. A single type of convertor cell may be cascaded to the desired number of quaternary output digits. The reference current that defines the full scale input range may be set externally. This circuit is input-output compatible with other previously described VLSI-compatible current-mode CMOS quaternary threshold logic and memory circuits.