Search

In-memory computing based on memristive logic is considered as a prospective non von Neumann computing paradigm. In this letter, we systematically analyze the four-variable logic method and map it into the operation of two anti-serial complementary memristors in the crossbar array architecture. Arbitrary Boolean logic can be implemented within three cycles with the experimental evidence of reconfigurable NAND, NOR, and XOR logic using Pt/HfO2/TiN devices. Taking advantage of the functional flexibility, a parallel 1-bit full adder that can be realized in 8 cycles within a $\textsf {4}\times \textsf {3}$ array has been designed and verified in simulation.

Nonvolatile stateful logic through RRAM is a promising route to build in-memory computing architecture. In this letter, a logic methodology based on 1T1R structure has been proposed to implement functionally complete Boolean logics. Arbitrary logic functions could be realized in two steps: initialization and writing. An additional read step is required to read out the logic result, which is in situ stored in the nonvolatile resistive state of the memory. Cascade problem in building larger logic circuits is also discussed. Our 1T1R logic device and operation method could be beneficial for massive integration and practical application of RRAM-based logic.

Resistive random access memory (RRAM) based reconfigurable logic provides a temporal programmable dimension to realize Boolean logic functions and is regarded as a promising route to build non-von Neumann computing architecture. In this work, a reconfigurable operation method is proposed to perform nonvolatile sequential logic in a HfO2-based RRAM array. Eight kinds of Boolean logic functions can be implemented within the same hardware fabrics. During the logic computing processes, the RRAM devices in an array are flexibly configured in a bipolar or complementary structure. The validity was demonstrated by experimentally implemented NAND and XOR logic functions and a theoretically designed 1-bit full adder. With the trade-off between temporal and spatial computing complexity, our method makes better use of limited computing resources, thus provides an attractive scheme for the construction of logic-in-memory systems.

RRAM is a promising candidate to construct in-memory computing architecture which can break through the von Neumann bottleneck. Taking advantage of the CMOS compatible 1T1R RRAM, functionally complete Boolean logics can be realized within two steps in a single unit that can suppress sneak pass problem and avoid cascading problem partially. In addition, an 8-bit pre- calculation adder with low computation complexity is designed and demonstrated experimentally to verify the feasibility and efficiency of 1T1R based in-memory computing architecture, which is applicable to future energy-efficient information processing systems.

We propose semi-analytical approaches for estimating the failure rate of interleaved error correction code (ECC) for parity-check (PC)-coded optical recording systems. We demonstrate the accuracy of the proposed approaches using simulation results. We further evaluate the ECC failure rate (EFR) of a PC-coded optical recording system. The analysis shows that with optimum interleaving degrees, the 4-bit constrained PC code achieves a gain of 0.6 dB over the rate 9/13 code without parity at EFR =10-16.