Performance Enhancement Counter with Minimal Clock Period

A synchronous binary counter is a fundamental component in VLSI design which are used commonly. synchronous binary counter is fast and are used in many applications as it supports wide bit-width. Due to large fan-outs and long carry chains many previous counters have low counting rate when the size of the counters is large. A new fast structure has been suggested for synchronous binary counter with a very low delay for counter with size ranging from 8 to 128 bits. To reduce the complexity of hardware a 1-bit Johnson counter has been used and then duplicate it to minimise propagation delay induced by large fan-outs. The suggested design is realised with a small number of flip-flops, using a back carry propagation counter and a counter based on state look ahead logic, which reduces power and delay

Design of a 1.9 GHz low-power LFSR circuit using the Reed-Solomon algorithm for Pseudo-Random Test Pattern Generation

A linear feedback shift register (LFSR) has been frequently used in the Built-in Self-Test (BIST) designs for the pseudo-random test pattern generation. The volume of the test patterns and test power dissipation are the key features in the large complex designs. The objective of this paper is to propose a new LFSR circuit based on the proposed Reed-Solomon (RS) algorithm. The RS algorithm is created by considering the factors of the maximum length test pattern with a minimum distance over the time. Also, it has achieved an effective generation of test patterns over a stage of complexity order O (m log2 m), where m denotes the total number of message bits. We analyzed our RS LFSR mathematically using the feedback polynomial function for an area-sensitive design. However, the bit-wise stages of the proposed RS LFSR are simulated using the TSMC 130 nm IC design tool in the Mentor Graphics platform. Experimental results showed that the proposed LFSR achieved the effective pseudo-random test patterns with a low-test power dissipation (25.13 µW). Ultimately, the circuit has operated in the highest operating frequency (1.9 GHz) environment.   &nbsp

Multistage Linear Feedback Shift Register Counters with Reduced Decoding Logic in 130-nm CMOS for Large-Scale Array Applications

Linear-feedback shift register (LFSR) counters have been shown to be well suited to applications requiring large arrays of counters and can improve the area and performance compared with conventional binary counters. However, significant logic is required to decode the count order into binary, causing system-on-chip designs to be unfeasible. This paper presents a counter design based on multiple LFSR stages that retains the advantages of a single-stage LFSR but only requires decoding logic that scales logarithmically with the number of stages rather than exponentially with the number of bits as required by other methods. A four-stage four-bit LFSR proof of concept was fabricated in 130-nm CMOS and was characterized in a time-to-digital converter application at 800 MHz. © 1993-2012 IEEE