#Qucs spice tutorial manual
#Qucs spice tutorial full
#Qucs spice tutorial simulator

The device models can be found in the primitive device models & cells library, in subdirectory cells. I keep this log since it might help identify problems for other people that try to reproduce this set-up. The corresponding files can be found here:īelow is a chronological log of my experiments to get Qucs-s and NGSpice to work with Skywater 130nm.

This is the schematic:Īnd this is the corresponding result page: In this example we are going to simulate the DC Vd/Vds curves with Vg as a parameter as well as the input (S11) and gain (S21) s-parameters. To simulate other process corners, reopen the sky130.lib file and change the last 'tt' to any of the other corners (ss, ff, sf or fs).Now you can add simulation blocks and probes as usual and run your simulation (hit F2) and inspect the results in the usual way (by placing tables, graphs etc.Note that the units in the current Sky130 PDK are micrometers! Params: 'w=1.0' (without the quotes) or similar parameters to define the size of your transistor.Sympattern: nmos4 or pmos4 (depending on the type of transistor that you are placing).Device: name of the transistor model that you want to use, such as sky130_fd_pr_nfet_01v8.File: dummy.spice (the empty file you created).Once you place such a transistor, double click and enter the following parameters: Now you can build a schematic like you would normally, except use 'SpiceLibComp' from the 'file components' drop down palette instead of transistors.Double click on the 'include' component and enter 'sky130.lib' (the 1-line file you just created) in the top field, to the right of 'File'.In the schematic, put an 'include' component from the 'Components' tab, it can be found by selecting 'SPICE specific sections' from the drop down menu at the top and is labeled 'Include statement'.Create a new schematic (menu 'File', 'new').Close both text files (click on the cross on the right side of the tabs).Create another new text file, leave it empty.End the line with 'tt' without quotes, and a new line.

#Qucs spice tutorial full

In this text file, enter a line consisting of '.LIB ' (without the quotes but with the trailing space) followed by the full or relative path to the file, and enclose this in double quotes.Within the new project, create a new text file (Menu 'file', 'new text').Within QUCS, create a new project (tab 'projects', button 'new').

#Qucs spice tutorial simulator

Also choose a convenient directory to store netlist and simulator outputs and apply changes.

In the window that will pop up, select 'Ngspice' as the default simulator and select the correct Ngspice executable location:

After installing NGSpice first and Qucs-s second, start Qucs-s and go to the simulator setup (menu: 'Simulation' entry: 'Select default simulator').

Please make sure this file exists and take note of the full or relative path to this file. It is named '' and can be found in the 'models' subdirectory.

We are going to use the 'skywater-pdk-libs-sky130_fd_pr-main' directory, and more specifically the crucial library file that links to all device models and process corners.

Unpack the skywater libraries in a convenient directory that should be accessible (through a full or relative path) from Qucs and NGSPice.Setting up Qucs-s + NGSpice for Skywater 130nm:

#Qucs spice tutorial manual

The user manual can be found here: ngspice user manual (sourceforge.io)

For simulation we use version 3.7 of ngspice: Ngspice downloads.

The user manual can be found here: Qucs-S Help documentation

For schematic entry we use version 0.0.024 of Qucs-s: Qucs-S: Qucs with SPICE ()ĭownloaded 20220718: qucs_s_win64_0_0_24.zip.

Primitive device models & cells library: GitHub - google/skywater-pdk-libs-sky130_fd_prĭownloaded 20220720: skywater-pdk-libs-sky130_fd_pr-main.zip.

Main Skywater PDK: skywater-pdk/libraries at main.

Skywater PDK documentation: SkyWater SKY130 PDK’s documentation.

Efabless foundry documentation, cost, access etc.:.

Skywater is a joint open source silicon project of Efabless and Google On this page you can find some info based on reverse engineering the PDK to enable the use of Qucs-s and NGSpice for open access IC design. The current PDK of Skywater for analog/RF design is rather incomplete.