Schematic Capture
Prerequisites:
- A rough design concept
- Design building blocks (optional)
- Keystone components
- Block diagram (optional)
Tools:
- Logical design tool (Schematic Capture EDA)
Next Step:
Once your block diagram, keystone components and design concept have solidified you’re ready to move on to schematic capture.
Schematic capture can seem daunting at first glance, but it’s really quite simple. It’s little more than a continuation of the block diagramming and white-boarding you did in ideation. You will probably use an ECAD, EDA or CAD package to design (also called capture) your schematic. This system will allow you to create parts, place and move them around on a canvas, and connect their pins together. A connection is called a net, and represents a electrical wire that will eventually be routed between these pins.
Your goal in schematic capture is to go from a blank canvas, to a set of building blocks, to a fully connected logical design. This logical design should “work”. It should generate power from other power, turn-on all parts that need power in the right order and connect to abstract inputs and outputs.
But for starters you just need to begin by adding your keystone parts and connecting them to each other on the right pins. The next step is to add the “glue” parts and start connecting them to everything else. And then come the passives, the filter caps and auxiliary components.
Most schematic editors work like you would expect. There are tools to add, move and remove parts. Tools to connect them together. Tools to edit part properties. And tools to check your work. Think of it as a topical, more specific, more granular mind mapping or block diagramming tool.
Your workflow:
- Add keystone parts
- Read datasheets re: power
- Connect their power
- Read datasheets re: communication buses
- Connect their buses
- Add “glue” parts
- Read datasheets
- Connect them to power and everything else
- Add filtering and other remaining parts
- Read datasheets
- Connect remaining pins
- Check & double check
As soon as parts of your schematic begin to solidify you can either begin doing simulations or start laying out your PCB.