During the process of IC test and verification, it is difficult
for test engineers to generate a valid test pattern named
automatic test pattern (atp) to perform in the Automatic Test
Equipment (ATE),including scan and functional test. Usually,
many IC design simulation tools output Value Change Dump
(VCD) format or Waveform Generation Language (WGL)
format as functional simulation. However, the VCD format is
not a good representation of the required test pattern for test
equipment, because it is "time-based" in nature and is quite difficult to be converted into the "cycle-based" test pattern for
chip testing purpose. The "tailoring" of VCD file is a common
nightmare experience to test engineers. Often, engineers
require some additional tools, for example Tetra MAX, to
generate the required test pattern from previous VCD files.
Tetra MAX is an automatic test pattern generation tool
provided by Synopsys, and one of its function is to generateatp
file from the simulation tools. However, the rent of Tetra MAX
is expensive, especially for college teachers and students.