XSCHEM
Schematic circuit editor for VLSI and Mixed mode circuit simulation.
...A VHDL, Verilog or Spice netlist can be generated from the drawn schematic, allowing the simulation of the circuit. Key feature of the program is its drawing engine written in C and using directly the Xlib drawing primitives; this gives top speed performance, even on very big circuits. I have succesfully managed to simulate complete VLSI projects with this tool, both digital (Verilog / VHDL) and analog (Spice).
Schematics can be printed in SVG, PNG, PDF, formats. XSCHEM runs on Linux or other Unix-likes with Xorg server and on Windows with the Cygwin layer and required tools installed.
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