linear feedback shift register circuit diagram

These circuits are used in Design for test (DFT), Built in SelfTest (BIST), cryptography and many more. A LFSR contains flipflops along with XOR gate as a feedback. LFSR is a shift register used to generate pseudo random patterns, which is used in pseudo random test applications of ASIC chips. Applications of D flipflop include data storage registers, data transferring shift registers, Linear Feedback Shift Registers, etc. A double edge triggered flipflop stores data on both the edges of a clock and the circuits, which store data either on one of the rising or falling edge is referred to as single edge-triggered flipflop.

In VLSI technology, low power requirement is one of the important factors. The CMOS D flipflop used in the place of buffers reduces delay as well as power consumption, which increases the performance of the circuit. D flipflop is mainly used to create delay lines in digital applications. D flipflops are bistable circuits in which D stands for “data”, it is the flipflop that stores data, which is a basic memory cell. Keywordsįlipflops are basic cells in many circuits of VLSI chips. The chip area is also reduced as it uses only four multibit flipflops in place of an eight D flipflop in the proposed design. The result analysis provides that the power of standard eight-bit LFSR is about 92,732.236 nW, and it is reduced to 35,217.804 nW as we use multibit flipflops to implement an eight-bit LFSR. The synthesis and physical design are carried out using Cadence Genus and Innovus tools. The proposed design simulation is done using the Xilinx IDE. The total design area is reduced due to the usage of the multibit flipflop without affecting the performance of the design. Multibit flipflop is used in applications where low power and area is the main concern. The proposed technique uses multibit flipflops for designing the LFSR. The standard implementation of LFSR uses D flipflops and exclusive OR connected linearly. The Linear Feedback Shift Register (LFSR) can be employed to generate pseudorandom patterns in test generators. In the emerging world of VLSI technologies, the challenges for the VLSI designers keep raising to produce circuits that consume low power, area and speed.

Linear feedback shift register circuit diagram