Abstract: A latching comparator and associated method are disclosed that utilize resonant tunneling diodes, or other two-terminal devices possessing regions of negative differential operating resistance in their current-voltage characteristics, and Schottky diodes to provide high speed and reliable analog to digital conversions. In one embodiment, the latching comparator includes a differential amplifier, resonant tunneling diodes, and cross-coupled resistors. The latching comparator may include mode selection circuitry having a track mode signal and a latch mode signal as inputs. In addition, the latching comparator may include a plurality of Schottky diodes connected in series with the resonant tunneling diodes and the cross-coupled resistors.

Abstract: A data storage device consisting of at least two series connected resonant tunneling diodes (RTD1, RTD2) with capacitors (C1 ,C2) coupled thereacross. By coupling a time varying voltage V(t) across the series connected diodes, one the diodes can be selectively switched from a state below its peak current to a stable point above its peak current. The diode which switches state is controlled by the slope of the time varying voltage V(t). Cells consisting of at least two or more resonant tunneling diodes may be connected in series and can store up to 2.sup.N binary states where N is the number of resonant tunneling diodes in the cell.