Sleep transistor distribution in row-based MTCMOS designs

- The Multi-Threshold CMOS (MTCMOS) technology has become a popular technique for standby power reduction. This technology utilizes high-Vth sleep transistors to reduce subthreshold leakage currents during the standby mode of CMOS VLSI Circuits. The performance of MTCMOS circuits strongly depends on the size of the sleep transistors and the parasitics on the virtual ground network. Given a placed net list of a row-based MTCMOS design and the number of sleep transistor cells on each standard cell row, this paper introduces an optimal algorithm for linearly placing the allocated sleep transistors on each standard cell row so as to minimize the performance degradation of the MTCMOS circuit, which is in part due to unwanted voltage drops on its virtual ground network. Experimental results show that, compared to existing methods of placing the sleep transistors on cell rows, the proposed technique results in up to 11% reduction in the critical path delay of the circuit.

• Type: Conference
• Year: 2007
• Where: GLVLSI
• Authors: Chanseok Hwang, Peng Rong, Massoud Pedram
• Keywords: Cell Rows, GLVLSI 2007, Sleep Transistors, Virtual Ground Network, VLSI