Logic built-in self-test
LBIST
Logic BIST
- The term LBIST is an acronym for Logic Built in Self Test. As the name implies LBIST stands for design structures in VLSI which tend to provide self test mechanism for Logic gates in the design. There are many genres of the designs which are available in this category, but almost all depend on generation of a pseudo random sequence of inputs which are set as stimulus for the design, while the response to this stimulus is captured in a MISR (Multiple input shift register). This MISR is used to generate a "signature”. This signature is unique in sense that each failure in the device would lead to a different value at the end of the whole process. The utility of LBIST has long been argued throughout the VLSI industry due to its random nature of testing. The utility of LBIST has been taken over in most cases by generation of ATPG (Automatic test Pattern Generation) methodology where there is a degree of deterministic nature in the approach. The most prominent LBIST structures which are used across the board are STUMPS and BILBO.