Distributed data-retention power gating techniques for column and row co-controlled embedded SRAM

In this paper, multi-mode data-retention power gating (P.G.) techniques are presented for embedded memories. These data retention power gating techniques are applied to embedded SRAM with distributed column and row co-controlled capabilities. The SRAM array is divided into blocks. Each block has a dedicated data-retention power gating device. The data-retention power gating devices are controlled by signals from both row and column decoders. Only the selected block is powered-on. Multi-mode power gating structures proposed in this paper can provide 2× to 20× memory cell leakage reduction while maintaining good static noise margin. Simulation results show that for a 64-bit wordline, the active power reductions for 32-bit, 16-bit, and 8-bit blocks are 59%, 79%, and 94%, respectively. All the simulations and physical layout are implemented in TSMC CMOS technology.