Linear Feedback Shift Register (LFSR) in verilog

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A Linear-feedback shift register (LFSR) is another variation of shift register whose input bit is a linear function (typically XOR operation) of its previous state. It is generally used as a pseudo-random number generator, whitening sequence, pseudo-noise sequence, etc.

LFSRs are frequently used as pseudorandom pattern generators to generate a random number of 1s and 0s. Each output of the LFSR is multiplexed with an ASIC input and, when the device is placed in the LFSR (test) mode, the random, high-toggle-rate patterns produced are extremely good for generating high-fault coverage.

The main advantage of LFSR is that it is simple to construct and it operates at very high clock speed, but its main drawback is that the inputs are given in bit serial. To overcome these drawbacks.