an open source PCB editor for Microsoft Windows, released under the GNU General Public License.

Schematic Constructor v1.0

How to make a schematic design

To prevent the player slider from obstructing the bottom panel with buttons, it is recommended to expand it to full screen when watching a video. The video shows flashing orange buttons on the bottom panel which means that the corresponding button has been pressed on the keyboard. But you can also click on it with the mouse if you prefer. Let’s go!

1) Run the executable file FreeCds.exe and select the File-> New menu. First specify the project folder and then enter the project name in the main line. The program will create a folder of the same name in which it will place your project. In the course of work, many different files associated with the project will appear in this folder. The Schematic Constructor can import parts from other projects by pressing the F1 button, and for this, all projects must be stored in a shared folder.

The new version of Schematic Constructor (1.1) has a parameter called “index to project folder”. It indicates the storage depth of the project relative to the main folder. By default, it is 1, but if your project is stored inide a folder of another project, then set the value to 2.

2) The Schematic Constructor comes with a template file, Template.cds, which has a frame with captions. Insert this file into your project to get started. You can edit the Template.cds file like a normal project, change this frame, and save. In Schematic Constructor you can attach any image in BMP or JPEG format to any polyline. The image takes the size of the rectangle that describes the polyline, so you can set the image to any size by changing the dimensions of the polyline. It should be noted that there is a fundamental difference between importing a BMP and a JPEG file. A JPEG file is uploaded with preservation of the entire color gamut and is supported by the built-in PDF printer, while BMP is uploaded as a background image, where the color of the first pixel in the file is replaced by the color of the working background of the program screen (for copying or other purposes), it is not printed … In this video, we are importing just such a picture.

3) This video shows you how to change the polyline layer and thickness. You can move any polyline on different layer, or add a new line by placing it on one of the following layers:

You can add up to 14 more back layers via the Project » Options menu.

After you have completely drawn your schematic design, you can select all the lines with a frame and give them the same thickness if you want.

4) In the Schematic Constructor, any polyline has 6 text attributes:

Therefore, if you see any text in the file, then know that it always belongs to the polyline (when the text is selected, the polyline is highlighted). You can set the polyline attributes through the Set Attr dialog box, first select the polyline segment and then press F1. When you assign a text attribute to the polyline, for example RefDes, the polyline is moved to the corresponding reserved layer Part Outline / if you enter the attribute Pin Name, then to the layer Pin line / if you enter the attribute Net Name, then in layer Net Polyline. So, there are 3 reserved layers where you cannot manually move the polyline.

5) Draw all the polylines of the part on the ownerless layer, set the pin name attribute on the corresponding polylines. Then select the entire group and set the RefDes, Value and Footprint attributes - and the part is ready. You can then import this part from another project, so as not to draw it again every time. The F1 button brings up a dialog box for importing parts from previous projects.

6) You can make another part from one part by copying and modifying it. Edit text attributes without going into the polyline attributes dialog box, but through the text properties dialog box. Click on the text and press F1. If you want to hide the text, then set it to zero size and thickness.

7) Enable drag mode by pressing the F2 button. In this mode, you can continuously drag from place to place any object, such as text. Grab RefDes if you want to move three part attributes at once in one click - RefDes, Value, Footprint.

8) You need to know that when the part is rotated by an angle not multiple of 90 degrees, the part may lose its snapping to the grid, but it rotates without graphic distortion. If you want to bind the vertices to the grid, then select the menu item Project » Adapt to grid, but graphics distortion is inevitable.

You can combine diodes into a merger. Select 4 diodes and press F2 (Add Merge). In the dialog box, enter a name for the merge, for example Diode Bridge. Now, when you click on any of the diodes, the entire group will be selected.

9) The tantalum capacitor graphic has a + symbol on one of the pins you see in the background picture. Add this text to the Description field in the polyline attributes dialog box. And in the following video, it will be shown how to edit an already finished part, i.e. add this text after you have grouped the objects into a part.

10) When you click on a part element, the entire part is selected at once. To select a separate segment of the polyline, disable the selection of the part on the selection mask in the left pane of the main window. Now you can go into the properties of each of the polylines.

Important information: in the mode of the disabled part selection mask, it is impossible to copy and paste the part. All objects will be copied as separate entities, not a part. When copying a pin in this mode, there is also no automatic check of the free pin number.

11) If you have selected a group of polylines to turn it into a detail, but the button for calling the polyline attributes dialog (F1) is absent, then this means that the selected group contains not only polyline segments but also vertices of the polylines. There is a simple way to ignore the selection of vertices and nodes - in the selection mask (on the left side of the window) you need to disable the selection of line vertices

12) To align the vertex of a line using the coordinates of another vertex, it is not at all necessary to enter them manually in the properties dialog box. Watch this video to see how.

13) This video shows how to draw a circle or oval using arcs.

14) When you click on any polyline, the program remembers some of its parameters (such as width, style, etc.), so that you can later draw a similar polyline using the F4 hotkey. So to start drawing the connections between the pins of the circuit, click on some line, then deselect and press F4 “repeat line”. Press F4 again to activate vertex magnetization. When drawing net polylines, magnetization helps to get to the vertex of the pin. In this video, you can see how the operator presses the F4 button twice in a row to turn on the polyline drawing mode and activate magnetization.

15) Press the F9 key to generate all networks on the current page. By default, the program will create network names in the NETxxxxx format. When a polyline segment is selected, press the N hotkey to highlight the entire net. A complete list of hotkeys can be found in the HELP menu

16) You can draw a net mark in the form of an arrow, square, diamond, etc., and assign a net name, for example + E, in the polyline properties, but it is important to know that connecting other polylines to such a mark can only be at the ends of the net mark polyline, and not in the middle … In any case, there is no reason to worry - the automatic design checker will not let you make a mistake.

17) Now in the PCB editor, click the File » Netlist Import menu item and select this netlist file.