A novel peripheral circuit for RRAM-based LUT

Abstract

Resistive random access memory (RRAM) is a promising candidate to substitute static random access memory (SRAM) in lookup table (LUT) design for its high density and non-volatility. RRAM cells are fabricated at backend CMOS process and have negligible area cost. However, the complex peripheral circuit design to satisfy performance and accuracy requirements becomes a major issue. In this work, we propose a novel peripheral circuit for RRAM-based LUT. A new decoding scheme that supports dynamic programming is introduced. Furthermore, the expanded RRAM crossbar array together with the latch comparator based sense amplifier can dramatically reduce design complexity, decrease area cost, and improve tolerance on process variations. Compared to a 6-input SRAM-based LUT, the proposed RRAM-based one cuts off 60.4% of layout area. The maximal operating frequency reaches 1GHz at 10mV input difference. Simulations also show that the proposed LUT functions properly even RRAM resistances deviates 20% from the design value.