28nm High-k Metal Gate 4kb SRAM-Based FIFO with Ripple Bit-Line

• Main Author: 劉皓軒
• Other Authors: 莊景德
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/t7w2u7

碩士 === 國立交通大學 === 電子工程學系 電子研究所 === 104 === Nowadays, the embedded memory operating in low voltage progressively becomes a major trend in System-On-Chip (SoCs) to reduce the dynamic and standby power for portable devices and for ultra-low power bio-medical and wireless sensor applications. This thesis presents a novel two-port disturb-free 9T SRAM-based FIFO with ripple read bit-line (RBL) and negative write bit-line (WBL) write assist structure to enhance subthreshold operation. As the process scales down, the wire delay little by little dominates the whole delay, especially for the subthreshold region. The proposed Ripple bit-line structure divide the bit-line into several segments by the ripple buffer. Therefore, the wire delay can be reduced apparently. Furthermore, due to the programmable property of FIFO, the Ripple bit-line structure can reduce the power consumption efficiently. The proposed 9T SRAM cell has independent single-ended RBL and WBL and bit-interleaving architecture for enhanced soft error immunity. A 4kb test chip is implemented in UMC 28-nm high-k metal gate (HKMG) CMOS technology. Measured full functionality is error-free from 0.9V down to 0.4V. The measured maximum operation frequency at 0.9V , tt corner and 25℃ is 1.1GHz..