I wrote some latex code to draw Deep networks for one of my reports. You can find it here: https://github.com/HarisIqbal88/PlotNeuralNet
Netron viewer is the best tool to draw your model architecture
I suppose you have a pretrained model stored in .h5 file.
We can use Powerpoint to get the job done.
Draw the diagram (3D rectangles and perspectives come handy) -> select the interested area on the slide -> right-click -> Save as picture -> change filetype to PDF -> :)