This is a library of electronic circuit symbols for drawing circuit diagrams on the computer (skip over to Downloads below). The symbols are prepared in the Scalable Vector Graphics (SVG) format using Inkscape. SVG is a free and open vector graphics format, and I hope its use will make the symbols accessible to more people. This work was motivated by the lack of a sufficiently comprehensive and stylistically consistent set of circuit symbol drawings in the public domain. The library will always be a work in progress, and symbols are added as the need arises in my own work.
Most circuit symbols are provided in 4 possible orientations as they might be needed in a circuit diagram, so you can copy-and-paste what you need without the hassle of manually rotating the symbol, which ruins the text labels. For each orientation, the text labels are positioned and the text justified in the correct way.
The appearance of the circuit symbols in this library is the result of deliberate consultation and incidental influence from several sources:
First and foremost are the circuit diagrams found in the technical literature of National Semiconductor (see a sample: AN-31 – Op ap circuit collection). These have exerted a profound influence on the visual style adopted for the symbols in this library. In my opinion, the symbols are well-proportioned, and the lines have a thickness that is optimal for visibility and visual impact. I have thus sought to emulate these qualities in my own renderings of the symbols.
Second, I have consulted IEEE Standard 315, which specifies the ‘correct’ appearance of circuit symbols. In many cases however, I have elected to deviate from the standard, after taking into account certain norms of usage, and my own personal preferences.
Third, this work was initially derived from the circuit symbol library produced by Matthew Beckler, which was really useful in getting everything started.
No rights are reserved. These SVG graphics are made for and belong to the public domain.
From personal experience, it seems rather difficult to find pretty circuit symbols in the public domain. Maybe as a result, many circuit diagrams I have encountered on the Internet are (according to my own opinion and taste!) rather aesthetically deficient. Most are likely the product of the ‘schematic capture’ component of PCB design software, and even the most advanced commercial ones seem to produce rather unsightly schematics. The most common problem is that the lines are too thin!
Having failed to locate schematic capture software that produce sufficiently pretty circuit diagrams, I decided to create a proper library of symbols myself as the next best alternative.