PCB design glossary
Schematic
AKA: schematics
The symbolic drawing of a circuit, showing components and how they connect electrically.
A schematic is the engineering drawing of a circuit. It captures intent — which parts are present, how they connect, what each net means — without saying anything yet about the physical layout.
Modern AI tools like PCBEditor can generate full schematics from a plain-English description, skipping the manual click-pin-to-pin step. The output is still a normal schematic that any other EDA tool can consume.
What a schematic contains
- Symbols: each component drawn by function, with numbered pins.
- Wires and labels that define the nets between pins.
- Power symbols such as GND and +3V3 that join rails across the drawing.
- Reference designators and values for every part.
- Notes, and sometimes several sheets joined by hierarchical labels.
From schematic to board
Each symbol is linked to a footprint. Running ERC checks the connections, then the tool extracts a netlist and hands it to layout, where the parts are placed and the connections routed. The BOM also comes from the schematic. That is why a mistake here travels all the way to the finished board.
AI tools such as PCBEditor can draft a schematic from a plain-English description. The output is a normal schematic you can review and edit, and it should be checked the same way as a hand-drawn one.
Habits that make schematics readable
- Signals flow left to right, with power at the top and ground at the bottom.
- Use labels instead of long wires that cross the whole sheet.
- Group circuits by function: power, microcontroller, connectors.
- Put decoupling capacitors next to the IC they serve.
Work it out with a free tool
Skip the blank sheet
Write what the circuit should do and get a schematic with real parts and named nets, editable before it becomes a PCB.
Generate a schematic