cschem - use cases

The "transistor" problem

Setup

• sch -> pcb flow
• generic (light) symbol in the schematics (e.g. a generic NPN)
• footprint attribute set to a generic footprint (e.g. a generic sot23)

Problems

• the pin numbering of the symbol is arbitrary
• the pin numbering of the footprint is arbitrary
• a footprint+NPN doesn't determine the pinout: there are various NPN devices with different pinouts with the same footprint
• number of logical pins may not match number of physical pins; unused pins, mutliple pins connected