A vlsi design and implementation of digital circuits in bist using test pattern generation

Abstract

The Very Large Scale Integration (VLSI) circuits become newlineimportant technology from the year 1980 onwards. In VLSI technology more newlinethan hundreds of millions of transistors are fabricated in a single circuit. The newlinemicroprocessors produced in 1994 has more than 3 million transistors and newlinemany millions of transistor are used in today s computers and electronics newlineappliances. The size of the electronic circuits are reduced day by day. The newlinereduction in size of VLSI circuits increases the probability of manufacturing newlinedefect and the IC becomes defect. The fault in IC in the manufacturing newlineprocess is unavoidable and needs to be identified. The testing of VLSI circuits newlinebecome inevitable to identify the fault integrated circuits.The external testing of VLSI circuits is old, complex and time consuming. The external testing VLSI circuits is also costly. The Built-in newlineSelf Test is a new technology, applied to the VLSI circuits to test condition of newlinethe circuits. The BIST structure consist of four major components such as test newlinepatter generator, circuit under test, output response analyser and BIST newlinecontroller. The Linear Feedback Shift Register (LFSR) is the major newlinecomponent of test pattern generator. LFSR is acting as test pattern generator newlinein most of the BIST structure. newline newline