Logic built-in self-test (or LBIST) is a form of built-in self-test (BIST) in which hardware and/or software is built into integrated circuits allowing them to test their own operation, as opposed to reliance on external automated test equipment.
The main advantage of LBIST is the ability to test internal circuits having no direct connections to external pins, and thus unreachable by external automated test equipment.
LBIST that requires additional circuitry (or read-only memory) increases the cost of the integrated circuit.
LBIST that only requires temporary changes to programmable logic or rewritable memory avoids this extra cost, but requires more time to first program in the BIST and then to remove it and program in the final configuration.
The two uses may be distinguished by considering whether the integrated circuit being tested has an internal array or analog functions.