Publication Date
2014
Document Type
Thesis
Committee Members
John M. Emmert (Committee Member), Robert E. W. Fyffe (Other), Saiyu Ren (Advisor), Raymond E. Siferd (Committee Member)
Degree Name
Master of Science in Engineering (MSEgr)
Abstract
High speed, low power, and area efficient adders and comparators continue to play a key role in hardware implementation of digital signal processing applications. Adders based on Complimentary Pass Transistor Logic (CPL) are power and area efficient, but are slower compared to Square Root Carry Select (SQRT-CS) based adders. This thesis demonstrates a unique custom designed 16-bit adder in 250-nm CMOS technology to obtain fast and power/area efficient features by combining CPL and CS logic. Comparing the results obtained for proposed 16-bit Linear CPL/CS adder with the BEC (Binary Excess-1 Code) based low power SQRT-CS adder, the delay is reduced by approximately one thirds, power is reduced by 19.2%, and the number of transistors is reduced by 23.4%. Also, new tree-based 64-bit static and dynamic digital comparators are presented in this thesis to perform high speed and low power operations. This tree-based architecture combines a new approach of designing dynamic comparator using a low duty cycle clock to reduce the short circuit power consumption in pre-charge (or pre-discharge) mode. This work also introduces a new sizing strategy and load balancing techniques to improve self-pipelining tendency of a tree based design. A resource sharing technique is also integrated in both static and dynamic comparator designs. At 1.2V power supply in CMOS 90nm technology, worst path delay and worst power are 374ps and 822µW, respectively for low cost static design with 1244 (768+476) transistors in total. 768 transistors are used for resource sharing. The proposed full and partially dynamic designs show superior power efficiency compared to recent state of art designs. The worst power consumptions at 5GHz and 25% (50ps) duty cycle clock for the 64-bit full and partially dynamic comparator designs are 5.00mW and 2.78mW, respectively. 769 (320+449) transistors includes 320 transistors for resource sharing, and 1217 (768+449) includes 768 transistors for resource sharing for full and partial dynamic comparators, respectively.
Page Count
75
Department or Program
Department of Electrical Engineering
Year Degree Awarded
2014
Copyright
Copyright 2014, some rights reserved. My ETD may be copied and distributed only for non-commercial purposes and may not be modified. All use must give me credit as the original author.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.