This paper proposes a post-layout transistor sizing method for crosstalk noise reduction. The proposed method downsizes the drivers of aggressor wires for noise reduction, utilizing the precise interconnect information extracted from the detail-routed layouts. We develop a transistor sizing algorithm for crosstalk noise reduction under delay constraints, and construct a crosstalk noise optimization method utilizing an analytic crosstalk noise model and a transistor sizing framework that have been developed. Our method exploits the transistor sizing framework that can vary transistor widths inside cells with interconnects unchanged. Our optimization method therefore never causes a new crosstalk noise problem, and does not need iterative layout optimization. The effectiveness of the proposed method is experimentally examined using 2 circuits. The maximum noise voltage is reduced by more than 50% without delay violation. These results show that the risk of crosstalk noise problems can be considerably reduced after detail-routing.

We present an efficient heuristic algorithm to reduce glitch power dissipation in CMOS digital circuits. In this paper, gate sizing is classified into three types and the buffer insertion is classified into two types. The proposed algorithm combines three types of gate sizing and two types of buffer insertion into a single optimization process to maximize the glitch reduction. The efficiency of our algorithm has been verified on LGSynth91 benchmark circuits with a 0.5 µm standard cell library. Experimental results show an average of 69.98% glitch reduction and 28.69% power reduction that are much better than those of gate sizing and buffer insertion performed independently.

We propose a transistor sizing method that downsizes MOSFETs inside a cell to eliminate redundancy of cell-based circuits as much as possible. Our method reduces power dissipation of detail-routed circuits while preserving interconnects. The effectiveness of our method is experimentally evaluated using 3 circuits. The power dissipation is reduced by 75% maximum and 60% on average without delay increase. Compared with discrete cell sizing, the proposed method reduces power dissipation furthermore by 30% on average.

This paper presents a new LP based optimal cell selection method. Optimal cell selection is useful tool for final tuning of LSI designs. It replaces drivabilities of cells, adjusting timing, area, and power constraints. Using the latest and earliest arrival times, it can handle cycle time optimization. We also make a useful initial basis, which speeds up a simplex LP solver by 5 times without any relaxations nor approximations. From experimental results, it can speed up a 13k-transistor circuit of a manual chip design by 17% without any increase of area.

In this paper, the power dissipation issue is considered in the gate sizing procedure. In order to observe the tradeoff among area, delar and power dissipation in a circuit, gate sizing algorithms which can minimize power under delay constraints or minimize area under power and delay constraints are formulated. Experiments are performed to investigate the properties of area–power–delay tradeoff in the gate sizing procedure.