DRAW ANALOG/DIGITAL circuits
Download Kicad
Use the symbol editor to load the analog library (ANALOG_DRAW.kicad_sym):
Use the schematic editor to draw your circuits :
- press A to select the components
- press R to rotate the components, X to mirror horizontally, Y to mirror vertically
- press CTRL-C/ CTRL-V to copy the components
- press W to create a wire
- press T to add text or node names
Click on File/Plot to export your work in PDF, SVG format ...
DRAW DIGITAL signals
Download WaveDrom
DRAW ANALOG signals
Use Octave if the signals are made up of basic functions (e.g. step, ramp, sine...)
Use Xfig if you need to draw complex spline signals
Use Inkscape to post-process the result.