<p>In comparison to other basic arithmetic operations, such as addition, subtraction and multiplication,division is far more complex and expensive. Many division algorithms, except for lookup tables, rely on recursion with usually complex operations in the loop. Even if the cost in terms of area and computational complexity sometimes can be made low, the latency is usually high anyway, due to the number of iterations required. Therefore, in order to find a faster method and a method that provides better precision, a non-recursive polynomial-based algorithm was developed by the Department of Electrical Engineering at Linköping University. </p><p>After having performed high-level modelling in Matlab, promising results were achieved for up to 32 bits of accuracy. However, since the cost model did not take in account other factors that are important when implementing in hardware, the question remained whether the division algorithm was also competitive in practice or not. Therefore, in order to investigate that, this thesis work was initiated. </p><p>This report describes the hardware implementation, the optimization and the evaluation of this division algorithm, regarding latency and hardware cost for numbers with different precisions. In addition to this algorithm, the common Newton-Raphson algorithm has also been implemented, to serve as a reference.</p>

In this thesis two versions of a single filter frequency masking narrow-band high-speed recursive digital filter structure, proposed in [1], have been implemented and evaluated considering the maximal clock frequency, the maximal sample frequency and the power consumption. The structures were compared to a conventional filter structure, that was also implemented. The aim was to see if the proposed structure had some benefits when implemented and synthesized, not only in theory. For the synthesis standard cells from AMS csx 0.35 mm CMOS technology were used.

In comparison to other basic arithmetic operations, such as addition, subtraction and multiplication,division is far more complex and expensive. Many division algorithms, except for lookup tables, rely on recursion with usually complex operations in the loop. Even if the cost in terms of area and computational complexity sometimes can be made low, the latency is usually high anyway, due to the number of iterations required. Therefore, in order to find a faster method and a method that provides better precision, a non-recursive polynomial-based algorithm was developed by the Department of Electrical Engineering at Linköping University. After having performed high-level modelling in Matlab, promising results were achieved for up to 32 bits of accuracy. However, since the cost model did not take in account other factors that are important when implementing in hardware, the question remained whether the division algorithm was also competitive in practice or not. Therefore, in order to investigate that, this thesis work was initiated. This report describes the hardware implementation, the optimization and the evaluation of this division algorithm, regarding latency and hardware cost for numbers with different precisions. In addition to this algorithm, the common Newton-Raphson algorithm has also been implemented, to serve as a reference.

<p>In this thesis two versions of a single filter frequency masking narrow-band high-speed recursive digital filter structure, proposed in [1], have been implemented and evaluated considering the maximal clock frequency, the maximal sample frequency and the power consumption. The structures were compared to a conventional filter structure, that was also implemented. The aim was to see if the proposed structure had some benefits when implemented and synthesized, not only in theory. For the synthesis standard cells from AMS csx 0.35 mm CMOS technology were used.</p>

<p>A fast and energy-efficient multiplier is always needed in electronics industry especially DSP, image processing and arithmetic units in microprocessors. Multiplier is such an important element which contributes substantially to the total power consumption of the system. On VLSI level, the area also becomes quite important as more area means more system cost. Speed is another key parameter while designing a multiplier for a specific application.</p><p>These three parameters i.e. power, area and speed are always traded off. Speaking of DSP processors, area and speed of MAC unit are the most important factors. But sometimes, increasing speed also increases the power consumption, so there is an upper bound of speed for a given power criteria. Considering the battery operated portable multimedia devices, low power and fast designs of multipliers are more important than area.</p><p>The design of a low power, high speed and area efficient multiplier is thus the goal of my thesis work. The projected plan is to instantiate a good design and modify it for low power and speed and prepare its layout using 90nm technology in Cadence®. For that purpose study has been performed on a number of research papers presented in section 7 and selected one of the architecture presented by Jung-Yup Kang and Jean-Luc Gaudiot. They presented a unique technique for power reduction in Wallace tree multipliers. They have proposed a method to calculate 2’s complement of multiplicand for final Partial Product Row (PPR) if using MBE technique. This method has been used in the design for speed enhancement and power reduction.</p><p>The ultimate purpose is to come up with such an architecture which is energy and area efficient than a conventional multiplier at the same performance level. This report describes the design and evaluation of new energy-efficient 32-bit multiplier architecture by comparing its power, performance and chip area to those of a conventional 32-bit multiplier. The report throws light on the basic principles and methods of binary multiplication process and also the power consumption issues related to multipliers. The new algorithm, which reduces the last negative signal in the partial product row is discussed to develop the new architecture. A power performance comparison is shown. The simulation results show that the new architecture is 46 % energy-efficient than a conventional multiplier at the same performance level. The number of transistors used is 34% less and also it consumes 25% less chip area in 90nm CMOS technology.</p>

A fast and energy-efficient multiplier is always needed in electronics industry especially DSP, image processing and arithmetic units in microprocessors. Multiplier is such an important element which contributes substantially to the total power consumption of the system. On VLSI level, the area also becomes quite important as more area means more system cost. Speed is another key parameter while designing a multiplier for a specific application. These three parameters i.e. power, area and speed are always traded off. Speaking of DSP processors, area and speed of MAC unit are the most important factors. But sometimes, increasing speed also increases the power consumption, so there is an upper bound of speed for a given power criteria. Considering the battery operated portable multimedia devices, low power and fast designs of multipliers are more important than area. The design of a low power, high speed and area efficient multiplier is thus the goal of my thesis work. The projected plan is to instantiate a good design and modify it for low power and speed and prepare its layout using 90nm technology in Cadence®. For that purpose study has been performed on a number of research papers presented in section 7 and selected one of the architecture presented by Jung-Yup Kang and Jean-Luc Gaudiot. They presented a unique technique for power reduction in Wallace tree multipliers. They have proposed a method to calculate 2’s complement of multiplicand for final Partial Product Row (PPR) if using MBE technique. This method has been used in the design for speed enhancement and power reduction. The ultimate purpose is to come up with such an architecture which is energy and area efficient than a conventional multiplier at the same performance level. This report describes the design and evaluation of new energy-efficient 32-bit multiplier architecture by comparing its power, performance and chip area to those of a conventional 32-bit multiplier. The report throws light on the basic principles and methods of binary multiplication process and also the power consumption issues related to multipliers. The new algorithm, which reduces the last negative signal in the partial product row is discussed to develop the new architecture. A power performance comparison is shown. The simulation results show that the new architecture is 46 % energy-efficient than a conventional multiplier at the same performance level. The number of transistors used is 34% less and also it consumes 25% less chip area in 90nm CMOS technology.

<p>Bit-parallel addition can be performed using a number of adder structures with different area and latency. However, the power consumption of different adder structures is not well studied. Further, the effect of pipelining adders to increase the throughput is not well studied. In this thesis four different adders are described, implemented in VHDL and compared after synthesis. The results give a general idea of the time-delay-power tradeoffs between the adder structures. Pipelining is shown to be a good technique for increasing the circuit speed.</p>

Bit-parallel addition can be performed using a number of adder structures with different area and latency. However, the power consumption of different adder structures is not well studied. Further, the effect of pipelining adders to increase the throughput is not well studied. In this thesis four different adders are described, implemented in VHDL and compared after synthesis. The results give a general idea of the time-delay-power tradeoffs between the adder structures. Pipelining is shown to be a good technique for increasing the circuit speed.