The theory of affordances

The Ecological Approach to Visual Perception

physical design electronics wikipedia in integrated circuit design physical design is a step in the standard design cycle which follows after the circuit design at this step circuit representations of, integrated circuit layout wikipedia integrated circuit layout also known ic layout ic mask layout or mask design is the representation of an integrated circuit in terms of planar geometric shapes, engineering courses concordia university concordia university http www concordia ca content concordia en academics graduate calendar current encs engineering courses html, peer reviewed journal ijera com international journal of engineering research and applications ijera is an open access online peer reviewed international journal that publishes research, telecommunications abbreviations and acronyms consultation erkan is pleased to provide this living document for unlocking the evergrowing vocabulary of abbreviations and acronyms of the telecommunications world, contents international information institute vol 7 no 3 may 2004 mathematical and natural sciences study on bilinear scheme and application to three dimensional convective equation itaru hataue and yosuke

Vlsi Physical Design From Graph Partitioning To Timing Closure

The present invention provides a system and method for generating circuit schematic that includes extracting connectivity data of a plurality of devices from a netlist, categorizing the plurality of devices into groups, placing Schematic Analog Placement Constraints on all the instances by identifying instances among the groups that match with a circuit template (in-built as well as user-specified), creating a BFS instance tree of tree instances, creating a two terminal device clusters and creating instance attachments. Using the constraints during grid based placement and eventually generated schematic which look like analog schematic.

System and method for circuit schematic generation

The Physical Design Methodology of Integrated Systems is increasing its relevance in deep submicron technologies due to the appearance of new problems related to electrical behavior and performance predictability. This paper presents some techniques to improve reliability and manufacturability by the use of some layout strategies. One main approach is the search of regular solutions as the use of a layout composed by a matrix of cells. It is discussed the effects of layout strategies in the design of reconfigurable systems.

Physical design methodologies for performance predictability and manufacturability

This paper presents a fast and effective approach to gate-version selection and threshold voltage, Vth, assignment. In the proposed flow, first, a solution without slew and load violation is generated. Then, a Lagrangian Relaxation (LR) method is used to reduce leakage power and achieve timing closure while keeping the circuit no or few violations. If the set of gate-versions given by LR produces a circuit with negative slack, a timing recovery method is applied to find near zero positive slack. The solution without negative slack is finally introduced to a power reduction step. For the ISPD 2012 Contest benchmarks, the leakage power of our solutions is, on average, 9.53% smaller than and 12.45% smaller than . The sizing produced using our approach achieved the first place in the ISPD 2013 Discrete Gate Sizing Contest with, on average, 8.78% better power results than the second place tool. With new timing calculation applied, this flow can provide, on average, an extra 9.62% power reduction compared to the best Contest results. This flow is also the first gate sizing method to report violation-free solutions for all benchmarks of the ISPD 2013 Contest.

Effective Method for Simultaneous Gate Sizing and $V$ th Assignment Using Lagrangian Relaxation

This work investigates the use of very deep pipelines for implementing circuits in FPGAs, where each pipeline stage is limited to a single FPGA logic element (LE). The architecture and VHDL design of a parameterized integer array multiplier is presented and also an IEEE 754 compliant 32-bit floating-point multiplier. We show how to write VHDL cells that implement such approach, and how the array multiplier architecture was adapted. Synthesis and simulation were performed for Altera Apex20KE devices, although the VHDL code should be portable to other devices. For this family, a 16 bit integer multiplier achieves a frequency of 266 MHz, while the floating point unit reaches 235 MHz, performing 235 MFLOPS in an FPGA. Additional cells are inserted to synchronize data, what imposes significant area penalties. This and other considerations to apply the technique in real designs are also addressed.

Design of very deep pipelined multipliers for FPGAs

Discrete gate sizing has attracted a lot of attention recently as the EDA industry faces the challenge of optimizing large standard cell-based circuits. The discrete nature of the problem, along with complex timing models, stringent design constraints, and ever-increasing circuit sizes, make the problem very difficult to tackle. Lagrangian Relaxation (LR) is an effective technique to handle complex constrained optimization problems and therefore has been successfully applied to solve the gate sizing problem. This article proposes an improved Lagrangian relaxation formulation for discrete gate sizing that relaxes timing, maximum gate input slew, and maximum gate output capacitance constraints. Based on such formulation, we propose a hybrid technique composed of three steps. First, a topological greedy heuristic solves the LR formulation. Such a heuristic is applied assuming a slightly increased target clock period (backoff factor) to better explore the solution space. Second, a delay recovery heuristic reestablishes the original target clock with small power overhead. Third, a power recovery heuristic explores the remaining slacks to further reduce power. Experiments on the ISPD 2012 Contest benchmarks show that our hybrid technique provides less leakage power than the state-of-the-art work for every circuit from the ISPD 2012 Contest infrastructure, achieving up to 24p less leakage. In addition, our technique achieves a much better compromise between leakage reduction and runtime, obtaining, on average, 9p less leakage power while running 8.8 times faster.

A Hybrid Technique for Discrete Gate Sizing Based on Lagrangian Relaxation

A method of producing a flexible timing-driven routing tree is provided. Two or more target nodes are sorted in accordance with data criticality. A source-sink grid is built from one or more source nodes and the two or more target nodes. An initial routing tree is built comprising the one or more source nodes. A routing tree generation algorithm is executed on the initial routing tree, utilizing the sorted two or more target nodes and the source-sink grid in accordance with a user-defined timing factor to construct a flexible timing-driven routing tree. The user-defined timing factor specifies an extent of isolation for a routing path from a given one of the one or more source nodes to a given one of the two or more target nodes.

Methods and Apparatus for Providing Flexible Timing-Driven Routing Trees

Net by net routing is still a very important technique used to make connections in VLSI circuits. The maze routing algorithms used for this purpose correspond to shortest path searches derived from basic BFS or from A*, with many dedicated improvements. This paper proposes the use of a new path search algorithm, LCS*, for routing individual connections in VLSI circuits. LCS* is a generic and simultaneous bidirectional heuristic algorithm which is faster than A* in most graph domains, such as VLSI routing grids. This is achieved by using dynamic estimation with the separation of computed values for open and closed nodes. Results show that the running time is reduced and little storage space is needed.

Marcelo Johann

Papers

Effective Method for Simultaneous Gate Sizing and $V$ th Assignment Using Lagrangian Relaxation

Design of very deep pipelined multipliers for FPGAs

A Hybrid Technique for Discrete Gate Sizing Based on Lagrangian Relaxation

Methods and Apparatus for Providing Flexible Timing-Driven Routing Trees

Net by Net Routing with a New Path Search Algorithm