4-bit Carry Look Ahead Adder Using MGDI Technique

Today's high-performance processor is built with arithmetic logic units that add and subtract key components. Design considerations related to low power and high performance digital VLSI circuits have become more prevalent in today's world. In order to develop low-power and high-performance processors, the designers need to design their adder circuits with the required speed and power dissipation for their applications. This topic introduces the concept of a adder using MGDI Technique. The Exact Speculative Carry Look Ahead Adder the use of the Modified-GDI (Modified-Gate Diffusion Input) is cautioned in this work. The delay, location and energy trade off performs a integral role in VLSI. We already comprehend that designs which are of CMOS fashion occupy extra area might also eat extra strength consumption. The switching conduct of the circuit reason the heating up of integrated circuits affects the working stipulations of the purposeful unit. The adders are the most important parts of countless applications such as microprocessors, microcontrollers and digital signal processors and additionally in actual time applications. Hence it is necessary to minimize the adder blocks to format a perfect processor. This work is proposed on a 16 bit carry seem to be in advance adder is designed through using MGDI gate and 4T XOR gates and a speculator blocks. The proposed MGDI raise Look Ahead adder occupies 68% much less region and the strength consumption and the propagation extend additionally considerably reduces when in contrast to the traditional carry Look Ahead adder why because the variety transistors extensively reduces from 1448 (Conventional) to 456 (Proposed CLA). The simulation consequences of the proposed format carried out in Xilinx. Keywords: Delay, power dissipation, voltage, transistor sizing.

Minimization of Binary Decision Diagrams for Systems of Completely Defined Boolean Functions using Algebraic Representations of Cofactors

In design systems for digital VLSI (very large integrated circuits), the BDD is used for VLSI verification, as well as for technologically independent optimization, performed as the first stage in the synthesis of logic circuits in various technological bases. BDD is an acyclic graph defining a Boolean function or a system of Boolean functions. Each vertex of this graph corresponds to the complete or reduced Shannon expansion formula. Having constructed BDD representation for systems of Boolean functions, it is possible to perform additional logical optimization based on the proposed method of searching for algebraic representations of cofactors (subfunctions) of the same BDD level in the form of a disjunction or conjunction of other cofactors of this BDD level. The method allows to reduce the number of literals by replacing the Shannon expansion formulas with simpler formulas that are disjunctions or conjunctions of cofactors, and to reduce the number of literals in specifying a system of Boolean functions. The number of literals in algebraic multilevel representations of systems of fully defined Boolean functions is the main optimization criterion in the synthesis of combinational circuits from library logic gates.

Incremental Automatic Correction for Digital VLSI Circuits

The impact of the recent exponential increase in complexity of digital VLSI circuits has heavily affected verification methodologies. Many advances toward verification and debugging techniques of digital VLSI circuits have relied on Computer Aided Design (CAD). Existing techniques are highly dependent on specialized test patterns with specific numbers increased by the rising complexity of VLSI circuits. A second problem arises in the form of large sizes of injecting circuits for correction and large number of SAT solver calls with a negative impact on the resultant running time. Three goals arise: first, diminishing dependence on a given test pattern by incrementally generating compact test patterns corresponding to design errors during the rectification process. Second, to reduce the size of in-circuit mutation circuit for error-fixing process. Finally, distribution of test patterns can be performed in parallel with a positive impact on digital VLSI circuits with large numbers of inputs and outputs. The experimental results illustrate that the proposed incremental correction algorithm can fix design bugs of type gate replacements in several digital VLSI circuits from ISCAS'85 with high speed and full accuracy. The speed of proposed Auto-correction mechanism outperforms the latest existing methods around 4.8x using ISCAS'85 benchmarks. The parallel distribution of test patterns on digital VLSI circuits during generating new compact test patterns achieves speed around 1.2x compared to latest methods.

FPGA Based Vehicle to Vehicle Communication in Spartan 3E

This paper presents economic and reconfigurable RF based wireless communication at 2.4 GHz between two vehicles. It implements digital VLSI using two Spartan 3E FPGAs, where one vehicle receives the information of another vehicle and shares its own information to another vehicle. The information includes vehicle’s speed, location, heading and its operation, such as braking status and turning status. It implements autonomous vehicle technology. In this work, FPGA is used as central signal processing unit which is interfaced with two microcontrollers (ATmega328P). Microcontroller-1 is interfaced with compass module, GPS module, DF Player mini and nRF24L01 module. This microcontroller determines the relative position and the relative heading as seen from one vehicle to another. Microcontroller-2 is used to measure the speed of vehicle digitally. The resulting data from these microcontrollers are transmitted separately and serially through UART interface to FPGA. At FPGA, different signal processing such as speed comparison, turn comparison, distance range measurement and vehicle operation processing, are carried out to generate the voice announcement command, warning signals, event signals, and such outputs are utilized to warn drivers about potential accidents and prevent crashes before event happens.