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What are LVS and DRC tools?

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What are LVS and DRC tools?

DRC is a major step during physical verification signoff on the design, which also involves LVS (layout versus schematic) checks, XOR checks, ERC (electrical rule check), and antenna checks.

How is DRC related to LVS?

A successful design rule check (DRC) ensures that the layout conforms to the rules designed/required for faultless fabrication. However, it does not guarantee if it really represents the circuit you desire to fabricate. This is where an LVS check is used.

What is LVS chip design?

Layout Versus Schematic (LVS) checking compares the extracted netlist from the layout to the original schematic netlist to determine if they match. The comparison check is considered clean if all the devices and nets of the schematic match the devices and the nets of the layout.

What are the inputs for LVS in VLSI?

Design inputs needed for running LVS are as follows:

  • Graphical database system (GDS) layout database of the design.
  • Schematic netlist of the design.
  • Cell definition file including Intellectual property files and standard cells.
  • Pad reference file.

What is layout in VLSI?

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 which correspond to the patterns of metal, oxide, or semiconductor layers that make up the components of the integrated circuit.

What is ERC check in layout?

What is ERC? ERC (Electrical rule check) involves checking a design for all well and substrate areas for proper contacts and spacing thereby ensuring correct power and ground connections.

What is layout verification in VLSI?

Physical verification is a process whereby an integrated circuit layout (IC layout) design is verified via EDA software tools to ensure correct electrical and logical functionality and manufacturability.

What are the two types of layout design rules in VLSI?

There is several levels of design rules:

  • well rules;
  • transistor rules;
  • contact rules;
  • metal rules;
  • via rules;
  • other rules.

What is meant by layout in VLSI?

What is PV in VLSI?

What is the difference between schematic and layout?

Layout versus schematic (LVS): It is a method of verifying that the layout of the design is functionally equivalent to the schematic of the design. It is important to note that DRC does not ensure the intended functionality of layout.

What is the difference between block diagram and schematic diagram?

A block diagram presents the flow or functional information about a circuit, but it is not a detailed depiction of the circuit. An electronic schematic diagram presents the detailed information about the circuit, each of its components, and how they are wired into the circuit.

How to compare layout and schematic netlists?

(Mathematically, the layout and schematic netlists are compared by performing a Graph isomorphism check to see if they are equivalent.) In most cases the layout will not pass LVS the first time requiring the layout engineer to examine the LVS software’s reports and make changes to the layout.

What is the difference between a schematic diagram and PCB layout?

Any designer that has not dived into the deep world of PCB design and may not be aware of the important differences between a schematic diagram and a PCB layout. To quote the great Eric Bogatin, the distinction between a schematic diagram and a PCB layout lives in the white space of your schematic.

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