built-in self-test (BIST)
A built-in self test, Built- In Self Test (BIST), is characterized by the fact that a circuit, device or system can test itself. This can be done online or offline: Online simultaneously with normal operation, during the initialization phase or within idle periods, Offline as a functional diagnostic test of the software and hardware or by means of feedback signal routing using Linear Feedback ShiftRegister( LFSR).
In terms of functionality, Built-In Self Test uses a Test Pattern Generator (TPG) to generate a test pattern and feed it to theDUT. The result is analyzed by the Output Response Analyzer (ORA). The test depth is determined by the test pattern generator and can be complete, pseudo-complete or pseudo-random.
BIST tests are divided into Logic BIST (LBIST) and Memory BIST (MBIST). LBIST was developed especially for random logics and typically works with a pseudo-pattern or pseudo-random generator( PRNG), which generates a random pattern with which the logical states arechecked. If the output states do not match the truth table, then the logic is operating incorrectly. MBIST is a test pattern for memory. It consists of a test circuit with which memory modules are read out and their output states are compared with a specified pattern. In addition to the two methods mentioned, there is also ABIST, which stands for Array BIST and Analog BIST. So for the self test of arrays and of analog ICs.
BIST tests are used in many electronic devices. For example, in entertainment technology devices, home electronics, alarm systems, medical electronics devices, household and measuring devices, and in motor vehicles.