Capturing Your Design Idea as a Schematic

Schematic Editor Settings and Templates

Before you start working with schematics, it is recommended to configure the settings of the schematic editor on the Schematic section pages of System Preferences (accessed by selecting File » System Preferences). On the Schematic – General page, you can define default units, schematic sheet size and other settings for a newly created schematic sheet.

Configure schematic settings for CircuitMaker in system preferences.

A new schematic sheet can be created by selecting the File » New » Schematic command (1). Settings for the current schematic document are configured in the Document Options mode of the Inspector panel (2). In the General region of the panel, you can select units and set the grids to enable easier placement of design objects. In the Page Options region (3), you can select an existing schematic sheet template (Template), choose from standard sheet sizes (Standard), or set non-standard dimensions (Custom).

Create a new schematic sheet and configure it in the Inspector panel.

Drawing & Editing Techniques

CircuitMaker tools allow you to capture electronic circuits of any complexity, from flat designs with a couple of components and connections, to complex hierarchical projects with structured connectivity across multiple sheets.

An example of a top schematic sheet of a multi-sheet hierarchical project.

Electrical and graphical objects of the schematic editor can be placed by using commands from the ribbon's Home | Circuit Elements region (1) and Home | Graphical Elements region (2), respectively. Properties of a placed object selected in the design space can be changed in the Inspector panel (3) or in the ribbon's Home | Font and Home | Appearance regions (4).

Use the schematic editor's objects and configure their properties to form the schematic sheets of your design.

There are some tools to facilitate your work with objects on a schematic sheet:

• Selection Filter – allows you to define object(s) that can be selected on the sheet. You can choose all object types (All Objects) or some specific object types (Components, Ports, Texts, etc.).

  
  Configure the Selection Filter to define which objects can be selected on schematic sheets.

• Selection from left to right – click and drag a blue rectangle from left to right to select only those objects that are completely within the selection rectangle.

  
  Click and drag a blue rectangle from left to right to select objects that are completely within the selection rectangle. Here is shown the selection rectangle. Hover the cursor over the image to see the set of objects selected with this rectangle.

• Selection from right to left – click and drag a green rectangle from right to left to select all objects that are within or touch the selection rectangle.

  
  Click and drag a green rectangle from right to left to select objects that touch the selection rectangle. Here is shown the selection rectangle. Hover the cursor over the image to see the set of objects selected with this rectangle.

• Spacebar / Shift+Spacebar – use to rotate the selection clockwise or counterclockwise by 90 ํ.
• M – use to change the location of the selection.
• Ctrl+Left Arrow / Right Arrow / Up Arrow / Down Arrow – use to move the selection to the left/right/up/down in increments of one snap grid unit.
• Shift+Ctrl+Left Arrow / Right Arrow / Up Arrow / Down Arrow – use to move the selected object left/right/up/down in increments of 10 snap grid units.

• Ctrl+C / Ctrl+V / Ctrl+X – standard shortcuts to copy, paste, and cut selected objects. Commands are also available from the right-click menu.

  
  Use the Cut, Copy, and Paste commands or standard shortcuts to manipulate objects on the schematic sheets.

Some other shortcuts useful when working in the schematic editor are listed in the Shortcuts section.

Component Search & Placement

During schematic capture, you can use CircuitMaker community components available through the Libraries panel. You can search for the required component by specifying the category and/or using the search box. If a component has a schematic/PCB model added (such components are listed with the  icon in the panel), this component can be placed on the schematic by dragging it or using the Place command from the component's right-click menu.

Place a community component on the schematic sheet from the Libraries panel.

Wiring the Circuit

To define connectivity between component pins, you can use the tools provided in the ribbon's Home | Circuit Elements region. At the most basic level, you can create that connectivity by drawing a wire from one component pin to another by using the Wire object – this is referred to as physical connectivity.

After launching the wire placement command, the cursor will change to a cross-hair. When the cursor is near a component pin's electrical point, a red connection marker (red cross) will appear at the cursor location. This indicates that the cursor is over a valid electrical connection point on the component.

Place wires to create connectivity between components.

If the wire is forming a corner in the wrong direction, press Spacebar to toggle the corner direction. Press Shift+Spacebar to cycle through the wire placement modes. Use the Backspace or Delete keys to remove the last wire segment placed.

Connection within a schematic sheet can also be formed by placing a short Wire and a Net Label on each component pin – this is referred to as logical connectivity. For power nets global for the entire design, such as GND or VCC, you can also use Power Port objects. Some power ports with predefined styles and values are available in the Home | Circuit Elements | Power Port drop-down.

A number of predefined power ports are available from the Power Port drop-down.

The Bus and Harness objects are used in more complex schematics. Buses are used to bundle a series of sequential nets, for example, an address bus or a data bus. Signal harnesses can be used to bundle any number of nets, buses and lower-level harnesses.

Multi-sheet Design

If the design does not fit onto a single schematic sheet, it can be spread over multiple sheets. Multi-sheet designs are implemented by placing a Sheet Symbol on the parent sheet, which represents and links to the child sheet. While you can place Sheet Symbols and define their properties manually, there are commands that allow you to build your multi-document structure quickly and efficiently. The commands you use will depend on your personal design methodology – which can be broadly classified as top-down, or bottom-up.

• To build the structure in a bottom-up fashion, select the Sheet Actions » Create Sheet Symbol From Sheet command from the schematic sheet's right-click menu (1). In the Choose Document to Place dialog (2), select the schematic sheet that will be represented as a Sheet Symbol. The Sheet Symbol will include a Sheet Entry to match each Port it finds (3). The documents structure changes will be shown in the project tree within the Projects panel (4).

  
  Use the Create Sheet Symbol From Sheet command to create a Sheet Symbol from an existing schematic sheet.

• To build the structure in a top-down fashion, you can place a Sheet Symbol that represents a child schematic sheet to be created, then add the required Sheet Entries, then use the Sheet Symbol Actions » Create Sheet From Sheet Symbol command. A new schematic sheet will be created below the nominated sheet symbol. Ports are added to the child sheet to match any Sheet Entries found in the Sheet Symbol.

  
  Use the Create Sheet From Sheet Symbol command to create a schematic sheet from a placed Sheet Symbol.

If Ports or Sheet Entries are added or removed at a later stage, they can be re-synchronized by using the Sheet Symbol Actions » Synchronize Sheet Entries and Ports command from the right-click menu of a Sheet Symbol. The Synchronize Ports To Sheet Entries dialog will open where the mismatches between the ports and the sheet entries are displayed. Use this dialog to ensure that all sheet entries on the sheet symbol are matched to ports on the referenced child sheet below, both in terms of name and I/O Type. Synchronization can performed by pushing properties of the selected sheet entry to the selected port or by pushing properties of the selected port to the selected sheet entry.

The Synchronize Ports To Sheet Entries dialog.

Design Requirements in Schematic

Design directives are objects that are placed on the schematic during design capture, providing a way of specifying instructions to be passed to the PCB. Design directive objects can be placed using the ribbon's Home | Circuit Elements | Directives drop-down:

• A Generic No ERC directive is placed on a node in the circuit to suppress Electrical Rule Check violations that are detected when the design is validated.
• A Differential Pair directive is used to define a differential pair object on the schematic. The two nets in the pair must each be identified by a common Net Label with the suffixes _N and _P, and a directive must be attached to each.
• A Net Class directive enables you to create user-defined net classes on the schematic. In the Parameter Set mode of the Inspector panel for a placed Net Class directive, change the Value of the Net Class Name parameter to the required name of the net class.

In properties of the selected Differential Pair or Net Class directive, a design rule can be added for the net to which the directive is attached. This rule will be transferred to the PCB during design synchronization.

Use design directives to specify additional requirements for the project.

Verifying the Design

When the schematic design is ready, you can then validate it by selecting Project | Validation | Validate (1). During validation, CircuitMaker checks the design for logical, electrical, and drafting errors in accordance with the settings on the Error Reporting and Connection Matrix tabs of the Project Options dialog (2). The errors and warnings found will be listed in the Messages panel (3). If there are no errors, the Compile successful, no error found message will be shown in the panel.

Perform design validation according to the configured project settings.

Shortcuts

While CircuitMaker provides an intuitive and user-friendly interface, you can become even more productive by using shortcut keys. Shortcut keys are more efficient than carefully positioning a mouse over a button or drilling through ribbons and menus.

The following is the list of some frequently used shortcut keys of the CircuitMaker's schematic editor:

• B – enter Bus placement mode.
• Shift+B – enter Bus Entry placement mode.
• C – open the Libraries panel.
• W – enter Wire placement mode.
• N – enter Net Label placement mode.
• P – enter Port placement mode.
• Shift+S – enter Sheet Entry placement mode.
• Alt+Shift+H – enter Harness Connector placement mode.
• Shift+H – enter Harness Entry placement mode.
• T – enter Text String placement mode.
• A – enter Arc placement mode.
• L – enter Line placement mode.
• R – enter Rectangle placement mode.
• G – cycle forward through your predefined snap grid settings.
• Shift+G – cycle backward through your predefined snap grid settings.
• Ctrl+Shift+G – turn the visible grid on or off in the current document.