Design of electronic circuit should be both economical and reliable. If we put weight on economy, reliability will be lessened vice versa. But in some cases, a Designer should do exact design looking down upon economy. Especially, in integrated circuit, we should design as exactly as possible without much tolerance. In my thesis, I have studied the method for the exact design without much consideration in economy, and I also have developed Monte carlo Simulation program which can be operated by new generation of pseudo random number. Here, in my study, I have found out that new generation of pseudo random number was much more superior to any methods suggested by orthers.