access icon free Low-power data encoding/decoding for energy-efficient static random access memory design

© The Institution of Engineering and Technology
Received 12/11/2018, Accepted 26/07/2019, Revised 10/05/2019, Published 07/08/2019

This study presents a new energy-efficient design for static random access memory (SRAM) using a low-power input data encoding and output data decoding stages. A data bit reordering algorithm is applied to the input data to increase the number of 0s that are going to be written into the SRAM array. Using SRAM cells which are more energy-efficient in writing a ‘0’ than a ‘1’ benefits from this, resulting in a reduction in the total power and energy consumptions of the whole memory. The input data encoding is performed using a simple circuit, which is built of multiplexers and inverters. After the read operation, data will be returned back to its initial form using a low-power data decoding circuit. Simulation results in an industrial and a predictive CMOS technology show that the proposed design for SRAM reduces the energy consumption of read and write operations considerably for some standard test images as input data to the memory. For instance, in writing pixels of Lenna test image into this SRAM and reading them back, 15 and 20% savings are observed for the energy consumption of write and read operations, respectively, compared with the normal write and read operations in standard SRAMs.

Inspec keywords: encoding; CMOS memory circuits; SRAM chips; low-power electronics; integrated circuit design

Other keywords: inverters; energy-efficient design; standard SRAM; SRAM cells; energy consumption; Lenna test image; static random access memory design; SRAM array; multiplexers; complementary metal oxide semiconductor technology; low-power data decoding circuit; write read operations; low-power data encoding-decoding; power consumption; low-power input data encoding; data bit reordering algorithm

Subjects: Memory circuits; Semiconductor storage; CMOS integrated circuits; Electrical/electronic equipment (energy utilisation)

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