Legalized method used for mixed height standard cell circuit design

A standard unit and circuit design technology, applied in CAD circuit design, calculation, electrical digital data processing, etc., can solve problems such as lack of theoretical basis, inability to ensure the quality of legalization, and partial angles of processing problems, etc.

Inactive Publication Date: 2017-07-21
FUZHOU UNIVERSITY
View PDF3 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] There are two problems in the existing legalization methods of mixed height standard units: (1) they all use heuristic method to legalize the units o

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Legalized method used for mixed height standard cell circuit design
  • Legalized method used for mixed height standard cell circuit design
  • Legalized method used for mixed height standard cell circuit design

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0056] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0057] This embodiment provides a legalization method for mixed height standard cell circuit design, such as figure 1 shown, including the following steps:

[0058] Step S1: represent the circuit as a hypergraph H={V, E};

[0059] Step S2: Align the cells to the nearest row that correctly matches the power rail;

[0060] Step S3: preprocessing the multiple row height standard unit, and expressing the legalization problem of the mixed height standard unit with a quadratic programming mathematical model;

[0061] Step S4: converting the quadratic programming problem into a corresponding linear complementary problem LCP;

[0062] Step S5: solve the LCP with the matrix splitting iterative method MMSIM based on the modulus;

[0063] Step S6: restore the multiple row height standard unit;

[0064] Step S7: place the unit with a method similar to Tetris....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a legalized method used for mixed height standard cell circuit design. The technical scheme of the method comprises the following key points: (1) according to a cell position sequence obtained according to a global layout, carrying out relaxation on the right boundary constraint of a layout area, and converting a legalization problem of a mixed height standard cell into a corresponding LCP (Linear Complementary Problem), wherein the legalization problem can be effectively solved by an existing optimization method; (2) carrying out decomposition on a matrix in the converted LCP in a proper way, and using MMSIM (Matrix MultiSplitting Iterative Method) to solve the converted LCP, wherein the proper matrix decomposition meets MMSIM convergence requirements, and meanwhile, calculation time is greatly quickened; and (3) by use of the method, simultaneously optimizing all cells instead of optimizing cells one by one, and considering the legalization problem from a global perspective. An experiment result indicates that an efficient and practical legalization result (especially for a large-scale living example) can be provided, and the requirement of a mixed height standard cell legalization stage of existing VLSI (Very Large Scale Integration) can be met.

Description

technical field [0001] The invention relates to the technical field of VLSI physical design automation, in particular to a legalization method for mixed height standard unit circuit design. Background technique [0002] With the increasing complexity of modern circuit designs, standard cells often produce different cell heights based on characteristics such as area, power, and speed. For example, taller cells can give greater driving force and better routability, while requiring greater area and power costs. Conversely, shorter cells have poorer driving force and routability, but require less area and power costs. Therefore, in order to meet various circuit design requirements, circuits of mixed-height standard cells have become more and more popular. Simple standard cells are designed as a single-row-height structure, while complex standard cells are designed as multiple The row height structure. [0003] A modern layout process usually includes three main stages: (1) gl...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G06F17/50
CPCG06F30/39G06F30/398G06F2111/10
Inventor 陈建利朱自然朱文兴
Owner FUZHOU UNIVERSITY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products