MULTIVALUED SRAM CELL USING RESONANT TUNNELING DIODES

A multivalued SRAM cell using a vertically integrated multipeak resonant tunneling diode (RTD) pair is described. Two RTD's in series can have 2N + 1 stable states. With this concept, a five-stable-states memory cell has been implemented with two 2-peak RTD's. Several designs are presented for a high-speed static random access multivalued memory using the folding characteristics of RTD's. The different designs are described and studied by comparing their power consumption under different conditions of device parameters and the switching speed. This paper shows that the proposed memory cell using a pair of multipeak RTD's yields the best result from the standpoint of size, power dissipation, and speed among the RTD memory cells discussed.