A Novel Four-Transistor SRAM Cell with Low Dynamic Power Consumption

This paper presents a novel CMOS four-transistor SRAM cell for very high density and low power embedded SRAM applications as well as for stand-alone SRAM applications. This cell retains its data with leakage current and positive feedback without refresh cycle. The new cell size is 20% smaller than a conventional six-transistor cell using same design rules. Also proposed cell uses two word-lines and one pair bit-line. Read operation perform from one side of cell, and write operation perform from another side of cell, and swing voltage reduced on word-lines thus dynamic power during read/write operation reduced. The fabrication process is fully compatible with high-performance CMOS logic technologies, because there is no need to integrate a poly-Si resistor or a TFT load. HSPICE simulation in standard 0.25μm CMOS technology confirms all results obtained from this paper.

Authors:

• Arash Azizi Mazreah
• Mohammad T. Manzuri Shalmani
• Hamid Barati
• Ali Barati

Keywords:

• Positive feedback
• leakage current
• read operation
• write operation
• dynamic energy consumption.

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