This is a strange rant I’m queuing up.
This is about circuit design and the process both before and after it.
The general process of making a circuit board that’s all populated and ready to buy goes kind of like this:
- Come up with an idea
- Draft of circuit idea
- Schematic (sometimes on a napkin)
- Choose components
- Enter schematic in a design tool
- Board layout
- Spin board and populate
- If you need to go back to step 2
Eventually you’ll finish. (if you’re lucky)
The issue I have is that going from 4 to 7 many times you have not one, but a number of similar components to choose from. Even beyond that, sometimes the same component comes in different packages.
Of all the tools I’ve been dicking around with there seems to be a bit of an inversion. You need to pick a package before you drop the part on your schematic. This isn’t as much of an issue with a lot of ICs, but when you get to passives or jellybean ICs you have choices. Unless you have other design constraints, if you spec out a 1nF cap, you can get that in any number of different sizes.
Why do you have to artificially constrain that at schematic capture time?!