Dia:
Dia is a free circuit diagram software that lets you create variety of technical circuit diagrams that includes circuit sketches, ER Diagrams, network diagrams, flowcharts, UML diagrams, logic diagrams, and more. It offers you grid-like drawing canvas along with multiple preset tools like  Text tool, Arc tool, Line tool, Modify Object, Text Editor, Magnifying tool, and many more, which you can use to create variety of custom diagrams. It provides you color palette and variety of styles to start and end drawing lines. This free circuit diagram software offers you various customization options, using which you can adjust line width, line color, line style, font size, font style, text color, and much more. The best part of this free circuit diagram software is that it offers you multiple export options like, TEX. DIA, SHAPE, DXF, EPS, EMF, BMP, GIF, JPEG, JPG, TIF, TIFF, PNG, VDX, and many more.
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