Semi-automatic Physical Implementation And Optimization Of The Regular Circuit

The IC design cycle is greatly reduced with the continuous improvement of EDA tools. Place-and-route algorithms of EDA tools have good physical implementation and optimization for random logic function block, but they cannot efficiently utilize the internal circuit regularity to achieve high-performance design for the complex regular structure.To solve these problems, we summarize and optimize the semi-automatic physical implementation methodology and process that well-defined the advantage of regularity. Semi-automatic physical implementation method has the advantage of using script to quickly implement manual placement of regular circuit, with the regularity placement to guide tools automatic routing, improve performance of regular circuit. Firstly, we excavate the regularity of the circuit from the RTL code, use the smallest repeating unit that can embody the regularity to establish circuit schematics, and extract gate- level netlist information containing circuit regularity by hand-built circuit instead of tools automatic synthesization. Then, according to the layout planning constraints of the circuit, we can determines the layout configuration and the absolute position of smallest repeating unit in the physical view, and then precisely calculate the relative spacing between the repeating unit, copy manual placement information of smallest repeating unit to other reusable unit with the script among the rapid completion of the manual placement of regular units. Finally, efficient physical design of the circuit can be achieved by regular placement to guide the automatic routing. Regular structure can be divided into one-dimensional and two-dimensional according to the data flow category.Datapath often organized into bit-slice in the internal, all the bit slices are identical or similar. The designers need to achieve a manual placement, and then its physical information repeated is called to quickly build the overall manual placement. This paper use address components of datapath as the experimental target, the method of Semi-automatic physical implementation is used in the physical implementation in the regularity of datapath, such components is reduced power consumption 3.62% and maximum timing 10.34%.Two-dimensional regular structure which is normally present in data exchange path. Crossbar switch requires the decoding array and choice array to complete function, with a typical two-dimensional regular array. EDA automatic placement algorithm can't handle complex logic arrays. Semi-automatic physical implementations can extract smallest repeating unit in a two-dimensional array, and then use the script to quickly implement the entire manual placement of two-dimensional array. This paper selects the crossbar switch with a regular structure as experimental target of two-dimensional regular structure, the regularity of such arrays will fully apply to the physical implementation process, so that power consumption decreased 26.37%, the largest timing decrease of 25.1%.In the design process of high-performance chip, the designer can optimize regular circuit by applying this method within the chip, assist in the optimization of the whole chip.