i-manager's Journal on Electronics Engineering (JELE)


Volume 4 Issue 3 March - May 2014

Research Paper

QCA Based Low Power Parallel Binary Adder/SubtractorUsing Reversible Logic Gates

A. G. Sasikala* , S. Maragatharaj**
* PG Scholar, ECE Department, Knowledge Institute of Technology, Salem, India
** Assistant Professor, ECE Department, Knowledge Institute of Technology Salem, India
Sasikala, A. G., and Maragatharaj, S. (2014). QCA Based Low Power Parallel Binary Adder/Subtractor using Reversible Logic Gates. i-manager's Journal on Electronics Engineering, 4(3), 1-8. https://doi.org/10.26634/jele.4.3.2673

Abstract

Quantum Dot Cellular Automata (QCA) is an emerging nanotechnology in the field of Quantum electronics for low power consumption and high speed of operational phenomenon. Such type of circuit can be used in many digital applications where CMOS [Complementary Metal Oxide Semiconductor] circuits cannot be used due to high leakage and low switching speed. Also, reversible logic is becoming a more and more prominent technology having its applications in low power CMOS, quantum computing, nanotechnology, and optical computing. Reversibility plays an important role when energy efficient computations are considered. By combining both of these low power and area efficient QCA technologies, the author can make a new generation low power system. In this paper, reversible eight-bit parallel binary adder/Subtractor using QCA has been proposed. This method reduces the total area used compared to the normal CMOS based structures and reduces power dissipation by using reversible logic gates.

Research Paper

Low Power dissipation of Ring Counter using Dual sleep Transistor approach

M. Balaji* , B. Keerthana**, K. Varun***
* Asstistant Professor, Department of EIE, Sree Vidyanikethan Engineering College, Tirupati, India
**-*** Student, Department of EIE, Sree Vidyanikethan Engineering College, Tirupati, India
Balaji, M., Keerthana, B., and Varun, K. (2014). Low Power Dissipation Of Ring Counter Using Dual Sleep Transistor Approach. i-manager's Journal on Electronics Engineering, 4(3), 9-13. https://doi.org/10.26634/jele.4.3.2674

Abstract

In CMOS [Complementary Metal Oxide Semiconductor] integrated circuits design, scaling is challenged by higher power consumption. The significant growth in power dissipation has occurred mainly due to the higher clock speeds in addition to the smaller process geometries. The transistor packaging density and functionality on a chip is improved by scaling. The speed and frequency of operation is increased due to scaling and hence higher performance is achieved. When the technology scales down, then the leakage current increases exponentially. In 90 nm and below technologies, leakage power constitutes 30-40% of total power dissipation. In this paper, a dual sleep transistor approach is used for reducing the power dissipation of ring counter circuit with minimum possible area. The simulations were done using Micro wind Layout Editor and DSCH [Digital Schematic Editor] software.

Research Paper

Effective Low Power And High Performance Of Multimodulus Prescaler

A. Silambarasan* , G. Dinesh Kumar**
* PG Scholar, M.E-VLSI Design, Knowledge Institute of Technology, Salem.
** Assistant Professor, M.E-VLSI Design, Knowledge Institute of Technology, Salem.
Silambarasan, A., and Kumar, G.D. (2014). Effective Low Power And High Performance Of Multimodulus Prescaler. i-manager's Journal on Electronics Engineering, 4(3), 4-19. https://doi.org/10.26634/jele.4.3.2675

Abstract

The high speed dual modulus prescaler is one of the important functional blocks in frequency synthesizers. The dual modulus prescaler design is the bottleneck of the synthesizer, as it operates at the highest frequencies and consumes more power than any other circuit blocks of the synthesizer. A dual modulus prescaler (also known as divide-by-N/N+1 counter) normally consists of a divide-by-2/3 prescaler unit followed by several asynchronous divide-by-2 units. Usually, dual modulus prescaler consists of Flip flops and some extra logic implemented using logic gates which determine the terminal count. Here an E-TSPC [Extended True Single Phase Clock] logic based divide-by-2/3 prescaler using pass transistor logic is suitable for low supply voltage (0.9V) and low power applications have been designed and implemented. Here the counting logic and the mode selection control are implemented using a single P-MOS transistor. Thus the critical path is reduced and also increases its working frequency. Simulation results show that, compared with the conventional TSPC [True Single Phase Clock] and E-TSPC based 2/3 prescaler designs as much as 46% in PDP, 24% in operation speed and 44% in area can be achieved by the proposed design. Also the proposed 2/3 prescaler are designed and implemented to design a 32/33 prescaler, 47/48 prescaler and a multimodulus 32/33/47/48 prescaler. The power dissipation of the proposed multimodulus prescaler is lesser than the existing multimodulus prescaler designs shown by the simulation results.

Research Paper

Efficient Implementation Of Gate Oxide With And Without Breakdown In SRAM – BISR For Word Oriented Memories

M. Devipriya* , S. Lavanya**, Aswin Tilak A.***
* Department of ECE, Knowledge Institute of technology, Anna University, Salem, Tamilnadu, India.
** Assistant Professor, Department of Electronics and Communication Engineering, Vedantha Institute of Technology, Villupuram Tamilnadu.
*** Ph.D Scholar, Jodhpur National University, Jodhpur, India.
.Devipriya, M., Lavanya, S., and Tilak, A.A. (2014). Efficient Implementation Of Gate Oxide With And Without Breakdown In SRAM – BISR For Word Oriented Memories. i-manager's Journal on Electronics Engineering, 4(3), 20-28. https://doi.org/10.26634/jele.4.3.2677

Abstract

Scaling of the CMOS [Complementary Metal Oxide Semiconductor] technology associated with gate oxide thickness has become a major barrier for the design of circuit in nanoscale Static Random Access Memory (SRAM), especially in lower voltages. The operation of SRAM arrays are critical in reducing the power consumption. The Gate Oxide Breakdown caused by excessive electric field in the gate oxide causes increased vulnerability of the circuit performance, during breakdown. The devices are characterized by increased minimum voltage due to increase the static write failure as the voltage decreases. The design circuits were schematized using the DSCH2 schematic design tool, and their layouts were generated with the Micro wind 2 VLSI layout CAD tool. The proposed structures are simulated using Xilinx ISE design suite.

Research Paper

Design of Ripple Carry Adder Using Constant Delay Logic

R. Kathiresan* , M. Thangavel**
* Department of ECE Department, Knowledge Institute of Technology, Salem.
** Department of ECE Department, Knowledge Institute of Technology, Salem.
Kathiresan, R. , and Thangavel, M. (2014). Design Of Ripple Carry Adder Using Constant Delay. i-manager's Journal on Electronics Engineering, 4(3), 29-34. https://doi.org/10.26634/jele.4.3.2678

Abstract

In this paper, Wallace tree multiplier using the constant delay logic style and less number of transistors were designed and analyzed. Constant Delay (CD) logic provides low power consumption and to adjust the window width of the clock pulse, CD logic produces quick output evaluation before the input arrival for operation. Using these features, performance is good compared to normal static and dynamic logic. In this design, the timing block and logic block are implemented to reduce the static power dissipation and also to reduce the unwanted glitch in the output. This experimental result shows smaller power consumption and reduced chip area compared to the existing design.