Close Menu
  • Analog Design
    • Latest Analog Layout Interview Questions (2025)
  • Digital Design
    • Digital Electronics Interview Question(2025)
    • Top VLSI Interview Questions
  • Physical Design
    • Physical Design Interview Questions for VLSI Engineers
  • Verilog
    • Verilog Interview Questions(2024)
  • Forum
Facebook Instagram YouTube LinkedIn WhatsApp
SiliconvlsiSiliconvlsi
Forum Questions Register in Forum Login in Forum
Facebook Instagram YouTube LinkedIn WhatsApp
  • Analog Design
    • Latest Analog Layout Interview Questions (2025)
  • Digital Design
    • Digital Electronics Interview Question(2025)
    • Top VLSI Interview Questions
  • Physical Design
    • Physical Design Interview Questions for VLSI Engineers
  • Verilog
    • Verilog Interview Questions(2024)
  • Forum
SiliconvlsiSiliconvlsi
Home»VLSI Design»Linear Feedback Shift Register
VLSI Design

Linear Feedback Shift Register

siliconvlsiBy siliconvlsiOctober 2, 2023Updated:May 19, 2024No Comments2 Mins Read
Facebook Pinterest LinkedIn Email WhatsApp
Share
Facebook Twitter LinkedIn Pinterest Email
Linear Feedback Shift Register
Linear Feedback Shift Register

What is a Linear Feedback Shift Register?

In a linear feedback shift register (LFSR), carry generation plays a crucial role. An LFSR is a type of shift register used for various purposes, including generating pseudo-random patterns and compressing responses in Built-In Self-Test (BIST) systems.

Here’s how to carry generation works in an LFSR

Initial State

The LFSR begins with an initial state, which consists of values stored in its flip-flops (memory cells). This initial state determines the sequence of bits the LFSR will generate.

Clock Synchronization

The flip-flops in the LFSR are synchronized by a common clock signal, ensuring that they change values at the same time.

Feedback Mechanism

The core of carry generation is the feedback mechanism. In this mechanism, the values in the flip-flops are processed using XOR operations (modulo-2 addition). The XOR network computes new values based on the current state and feedback values. These new values are then shifted into the flip-flops.

Sequence Generation

As the LFSR shifts bits and computes new values through feedback, it generates a sequence of bits over time. This sequence depends on the initial state and the specific feedback polynomial used.

Repetition

LFSRs are designed to generate sequences that repeat after a certain number of clock cycles. The length of this sequence is determined by the number of flip-flops in the LFSR and the feedback polynomial.

What is Carry Generation?

Carry Generation refers to the process by which the register generates and propagates values or bits within itself. In particular, it involves the generation of new bits based on the current state of the register and its previous values, often involving mathematical operations like addition or exclusive-OR (XOR).

The key idea is that an LFSR can autonomously generate a sequence of bits that appears random but is entirely determined by its initial state and feedback polynomial. The carry generation process is what allows it to create this sequence efficiently.

Share. Facebook Twitter Pinterest LinkedIn Tumblr Email

Related Posts

How Shielding Avoids Crosstalk Problem? What Exactly Happens There?

September 22, 2024

Navigating the Challenges of Gate Dielectric Scaling in MOS Transistors

August 1, 2024

Challenges in Modern SoC Design Verification

April 20, 2024
Leave A Reply Cancel Reply

Facebook X (Twitter) Instagram Pinterest Vimeo YouTube
  • About Us
  • Contact Us
  • Privacy Policy
© 2025 Siliconvlsi.

Type above and press Enter to search. Press Esc to cancel.