vlsiphysicaldesign

Sanity checks are a crucial step before beginning the physical design flow in VLSI. These checks ensure that the inputs received from the library team and the synthesis team are correct and free of errors. Neglecting these checks can lead to significant issues in the later stages of design. Let's explore the essential sanity checks performed before starting the physical design flow. Design/Netlist Checks These checks verify the quality and consistency of the netlist. Key aspects include: Floating Pins : Ensuring there are no pins in the design that are not connected to any net. Multidriven Nets : Checking for nets driven by multiple sources, which can lead to contention. Undriven Input Ports : Ensuring all input ports have driving sources. Unloaded Outputs : Verifying that all outputs have loads connected. Unconstrained Pins : Ensuring all pins have constraints defined. Pin Mismatch Counts : Checking for discrepancies between the pins of an instance and its reference. Tristate Buse...

  Physical design in VLSI (Very Large Scale Integration) is a critical phase where a circuit's logical design (netlist) is converted into a physical layout. This layout is crucial for chip fabrication and must meet all design specifications, including timing, power, and area constraints. Here, we delve into the primary inputs required for physical design, accompanied by images to illustrate key concepts. 1. Netlist (.v) Format: Verilog (.v) Provided by: Synthesis Team The netlist is a textual representation of the circuit's components (logic gates, combinational and sequential circuits) and their interconnections. It defines the logical connectivity and can include components like resistors, capacitors, and transistors. Example Verilog Netlist: verilog module and_gate(y, a, b); input a, b; output y; AND2 U1 (.Y(y), .A(a), .B(b)); endmodule 2. Synopsys Design Constraints (SDC) Format: .sdc (written in TCL) Provided by: Synthesis Team SDC files include timing constraint...