Exploring the Heart of VLSI Design: Introducing Netlist!
What is Netlist
Netlist, a crucial representation in VLSI design, outlines the connectivity of an electronic circuit in textual format. It defines the interconnections between components like transistors, gates, and flip-flops, enabling complex tasks within a chip.So, netlist is a list of nets that describe how standard cells are connected to one another to create a specific design. Like the way, for an analog design, a netlist contains transistors, capacitors and resistors in the design.
There are 2 types of netlists:
- Flat netlist
- Hierarchical netlist
Flat netlist
There is only one module that holds all the information about the design.
Hierarchical netlist
It contains several modules, and one module calls these modules.
Example netlist:
module flop (clk, reset, next_clk_enable, clk_enable);
input clk, reset, next_clk_enable;
output clk_enable;
wire clk, n_3, next_clk_enable;
wire clk_enable;
DFFSHQX1 clk_enable_reg_reg(.SN (n_3), .CK (clk), .D (next_clk_enable), .Q (clk_enable));
endmodule
Importance of Netlist in VLSI
As VLSI devices grow in complexity and size, accurate and efficient communication between components becomes essential. The Netlist, a compact and hierarchical data structure, acts as a bridge between the high-level design (RTL) and facilitates vital tasks like simulation, synthesis, verification, and place-and-route.
