Built-in Self Test (BIST) :

As the complexity of VLSI circuits and as overall system complexity increases, test generation and application becomes an expensive and not always very effective means of testing. Further there are also very difficult problems associated with the high speeds at which many VLSI systems are designed to operate. Such problems require the use of very sophisticated, but not always affordable, test equipments. Built-in Self Test (BIST) is another solution. Figure below shows the Built-in Self Test system

 

 

 

Advantages :

• Lower cost due to elimination of external tester
• In-system, at-system, high-quality testing
• Faster fault detection, ease of diagnosis
• Overcomes pin limitations and related interfacing problems
• Reduces maintenance and repair costs at system level.