The main goal of Design for Testability (DFT) is to offer a way to test each node in the design (Netlist) for different kinds of defects in the chip. These nodes that are to be checked by using the intended number of patterns, the more thoroughly the design has been tested. Every node in the architecture must be visible(observable) and controlled for this to be achievable. These two concepts may be thought of as the cornerstones of DFT, which must be adhered to in order to get the most test coverage with the fewest possible patterns. This work is applied in the field of IC manufacturing before IC gets fabricated. The parameters like multi-voltages and temperature of IC will be determined with the help of Scan Insertion, ATPG pattern generation, EDT test compression and simulation using mentor graphics tool. In this script we are mainly concentrated on the compression process of the data volume and test time by generating automatic test patterns according to it and simulatingÂ