119 research outputs found
Satisfiability Modulo Theory based Methodology for Floorplanning in VLSI Circuits
This paper proposes a Satisfiability Modulo Theory based formulation for
floorplanning in VLSI circuits. The proposed approach allows a number of fixed
blocks to be placed within a layout region without overlapping and at the same
time minimizing the area of the layout region. The proposed approach is
extended to allow a number of fixed blocks with ability to rotate and flexible
blocks (with variable width and height) to be placed within a layout without
overlap. Our target in all cases is reduction in area occupied on a chip which
is of vital importance in obtaining a good circuit design. Satisfiability
Modulo Theory combines the problem of Boolean satisfiability with domains such
as convex optimization. Satisfiability Modulo Theory provides a richer modeling
language than is possible with pure Boolean SAT formulas. We have conducted our
experiments on MCNC and GSRC benchmark circuits to calculate the total area
occupied, amount of deadspace and the total CPU time consumed while placing the
blocks without overlapping. The results obtained shows clearly that the amount
of dead space or wasted space is reduced if rotation is applied to the blocks.Comment: 8 pages,5 figure
The generalized 3-connectivity of Cartesian product graphs
The generalized connectivity of a graph, which was introduced recently by
Chartrand et al., is a generalization of the concept of vertex connectivity.
Let be a nonempty set of vertices of , a collection
of trees in is said to be internally disjoint trees
connecting if and for
any pair of distinct integers , where . For an integer
with , the -connectivity of is the
greatest positive integer for which contains at least internally
disjoint trees connecting for any set of vertices of .
Obviously, is the connectivity of . Sabidussi showed
that for any two connected graphs
and . In this paper, we first study the 3-connectivity of the Cartesian
product of a graph and a tree , and show that if
, then ;
if , then .
Furthermore, for any two connected graphs and with
, if , then ; if , then
. Our result could be seen as
a generalization of Sabidussi's result. Moreover, all the bounds are sharp.Comment: 17 page
Design of Digital Parity Generator Layout Using 0.7 micron Technology
The proposed digital parity generator circuit is an integrated circuit functions to detect data errors at the transmitter end, and check it at the receiving end. In digital communications, the digital messages are transmitted in the form of 1’s and 0’s between two points. It is an error free if both are the same. The purpose of this research is to implement a design method of digital parity generator layout with 0.7 micron process technology ECPD07 from Tanner Tools. Layout design starts from making schematic circuit, test function and make a layout. Next, check the layout results in terms of design rules and verify the desired functionality gradually. The results show that the circuit has functioned well as an odd parity generator. The simulation results obtained with loads CL = 25 fF, tpLH = 2nS and tpHL = 1.46 nS indicate that tp = 1.73nS or operating frequency of 578 MHz. The integrated digital parity generator circuit using transmission gate has a size of 14758 um2 (78.5 um x188 um), consisting of 74 gates
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