cells off characters

The number of characters available on a CP aperture mask 440

Synopsys Library Compiler.

projection system in exchange for more design flexibility.

Table 12. Specification of projection equipment

High performance cell

Table 13. Two cell library description

**4.3.2 Experimental results** 

cell libraries.

starts with the generation of a cell library for the CP lithography. The cell library for the CP can be directly applied to a commercial logic synthesis tool. Once ASIC designers obtain the cell library for the CP, they can logic-synthesize their circuit in the same manner as the typical logic synthesis flow.

Fig. 11. Design flow in our design framework

In the design framework, a conventional cell library, the number of EB shots for every cell function, and a projection method for every cell function are required for generating a cell library specialized in the CP. The optimal projection method for every cell function can be obtained with the cell library development methodology, which we proposed in the previous work (Sugihara et al., 2005, 2006a). The simplified procedure for choosing the optimal projection method for every cell function is summarized as follows.


To obtain the projection method for every cell functions, we have utilized a benchmark circuit, b19 from the ITC'99 benchmark circuit suite (Davidson, 1999), as a referential circuit. The benchmark circuit has been logic-synthesized to minimize its area and then the mathematical problem instance has been solved for its netlist with a commercial ILP solver (ILOG, 2003).

We adopted commercial EDA tools as possible as we could in order to reduce software development. For the design framework, we have adopted the Synopsys Design Compiler as a logic synthesis tool and the Synopsys Library Compiler as a cell library generation tool. A cell library specialized in the CP (written in the Synopsys ".lib" format) has been generated with the following three things: a conventional cell library (also written in the

starts with the generation of a cell library for the CP lithography. The cell library for the CP can be directly applied to a commercial logic synthesis tool. Once ASIC designers obtain the cell library for the CP, they can logic-synthesize their circuit in the same manner as the

> Projection method for each cell

> > Logic synthesis (design\_compiler)

Technology-mapped circuit

Circuit (ITC99 benchmark)

In the design framework, a conventional cell library, the number of EB shots for every cell function, and a projection method for every cell function are required for generating a cell library specialized in the CP. The optimal projection method for every cell function can be obtained with the cell library development methodology, which we proposed in the previous work (Sugihara et al., 2005, 2006a). The simplified procedure for choosing the

Cell library development flow Logic synthesis flow

1. Obtain the reference counts of all cell functions, their numbers of EB shots to project a cell instance with the CP and VSB lithographies, and the number of characters available

2. With the above numbers, solve the mathematical problem instance shown in the previous work (Sugihara et al., 2005, 2006a). A solution to the mathematical problem

To obtain the projection method for every cell functions, we have utilized a benchmark circuit, b19 from the ITC'99 benchmark circuit suite (Davidson, 1999), as a referential circuit. The benchmark circuit has been logic-synthesized to minimize its area and then the mathematical problem instance has been solved for its netlist with a commercial ILP solver

We adopted commercial EDA tools as possible as we could in order to reduce software development. For the design framework, we have adopted the Synopsys Design Compiler as a logic synthesis tool and the Synopsys Library Compiler as a cell library generation tool. A cell library specialized in the CP (written in the Synopsys ".lib" format) has been generated with the following three things: a conventional cell library (also written in the

optimal projection method for every cell function is summarized as follows.

Cell library for character projection (.lib format)

Cell library generation depending on the priority among area and EB shots (software developed by the authors)
