uSimmics (formerly QucsStudio) is a powerful tool supporting analog and digital circuit simulation. Configuring it correctly from the outset dramatically improves the efficiency of your daily simulation workflow.
This article provides a detailed walkthrough of the two main configuration categories — Document Settings and Application Settings — covering every tab and option within each.
What You Will Learn
- The configuration options in the Document Settings tabs: Simulation, Grid, and Frame
- The configuration options in the Application Settings tabs: General, Text Editor, and Compiler
- The meaning of each parameter in the font specification string
- Key recommended settings to boost your productivity
- How to create clean, well-organized schematics using Grid and Frame
Document Settings
Document Settings are tied to individual schematic files. Each schematic can have its own independent configuration.
1. Simulation Tab
Controls how simulation results are displayed and saved.
| Setting | Description |
|---|---|
| Data Display | Specifies the file used to display simulation results. Defaults to *.dpl, but can be changed to any file |
| Data Set | Specifies the dataset filename where simulation results are stored. Useful for result reuse and managing multiple result sets |
| Open data display after simulation | When checked, the data display file opens automatically once simulation completes |
Recommendation: Enable “Open data display after simulation” to eliminate the need to manually open the results file after each run.
2. Grid Tab
Configures the grid (lattice lines) displayed on the schematic canvas.
| Setting | Description |
|---|---|
| Show Grid | Toggles grid visibility. Enabling it makes accurate component placement significantly easier |
| Horizontal Grid | Sets the horizontal grid spacing in pixels (default: 10) |
| Vertical Grid | Sets the vertical grid spacing in pixels (default: 10) |
Recommendation: Keeping the grid enabled is strongly advised. It reduces component misalignment and helps produce tidy, professional schematics.
3. Frame Tab
Adds a frame (title block border) to the schematic, giving it the appearance of a formal engineering drawing. Particularly useful for sharing drawings within a team or maintaining document records.
| Setting | Description |
|---|---|
| Frame Size | Selects the paper size and orientation (e.g., DIN A4 landscape) |
| Title | Enters the drawing title. Using a project or circuit name makes identification straightforward |
| Drawn By | Enters the author’s name |
| Date | Enters the creation date |
| Revision | Enters the revision number. Useful for tracking design change history |
Application Settings
Application Settings are global settings that apply to the entire uSimmics (formerly QucsStudio) application.
1. General Tab
Configures the fundamental behavior of the interface and simulation engine.
| Setting | Description |
|---|---|
| Document Font | Sets the font used in schematics and data display windows |
| Document Background Color | Changes the schematic background color. Adjust to suit your visual preferences |
| Language | Sets the UI display language. Available options are English and German (Japanese is not supported) |
| Maximum undo operations | Sets the maximum number of undo steps (default: 50). Consider increasing this for large-scale projects |
| Number of CPUs (for HB only) | Specifies the number of CPU cores used for Harmonic Balance (HB) analysis. Increasing this on multi-core systems accelerates analysis |
Reading the font specification string:
The font settings in uSimmics (formerly QucsStudio) use a string such as Arial,-1,16,5,50,0,0,0,0,0. The meaning of each value is as follows.
| Position | Example value | Meaning |
|---|---|---|
| 1 | Arial | Font name |
| 2 | -1 | Character set (-1 = system default) |
| 3 | 16 | Font size (points) |
| 4 | 5 | Font weight (5 = normal) |
| 5 | 50 | Stretch (50 = normal width) |
| 6 | 0 | Italic (0 = off, 1 = on) |
| 7 | 0 | Anti-aliasing (0 = off) |
| 8 | 0 | Underline (0 = none, 1 = enabled) |
| 9 | 0 | Strikethrough (0 = none, 1 = enabled) |
2. Text Editor Tab
Configures the font and syntax highlighting for the built-in text editor in uSimmics (formerly QucsStudio). These settings are especially important when writing VerilogA or SPICE model code.
| Setting | Description |
|---|---|
| Text Editor Font | Sets the font and size used in the text editor |
| Size of Tabulator | Sets the tab width (default: equivalent to 4 spaces) |
| Colors for Syntax Highlighting | Assigns colors to code elements such as comments, strings, and numbers. Color coding significantly improves readability |
3. Compiler Tab
Configures compilation settings for C++ and VerilogA models. These settings are required when creating or using custom component models.
| Setting | Description |
|---|---|
| Command line for executable | Specifies the path to the compiler executable and any command-line options |
Note for general users: If you are not using custom models, no changes to the Compiler tab are necessary.
Summary
The initial setup of uSimmics (formerly QucsStudio) is organized into two layers: Document Settings and Application Settings. Even configuring just the grid (Grid tab) and automatic post-simulation display (Simulation tab) can yield a substantial improvement in everyday workflow efficiency. Review the settings described in this article and customize them to fit your working environment.
Related Articles
- uSimmics (formerly QucsStudio) Overview and Getting Started [Introduction]
- How to Install Older Versions of uSimmics (formerly QucsStudio) [2026]
- uSimmics (formerly QucsStudio) Circuit Editor Basic Operations Guide [2026]
- How to Change the Project Folder Location in uSimmics (formerly QucsStudio)
- DC Analysis with uSimmics (formerly QucsStudio) [2026]
Comment