PCB design glossary
Netlist
The list of every electrical connection (net) in a circuit, derived from the schematic.
A netlist is the bridge between schematic and PCB layout. It enumerates every net, the pins on that net, and any net properties (class, width, layer constraints). The layout tool reads the netlist and uses it to constrain routing.
A schematic without a verified netlist is dangerous — it's where most missed connections and shorts come from.
What a netlist looks like
At its simplest, a netlist is a list of nets, and for each net the component pins on it: GND joins U1 pin 4, C1 pin 2 and J1 pin 1. EDA tools write it in their own formats, such as KiCad's netlist file or the Specctra DSN used by external routers, but the content is the same list of connections.
Checks worth running on a netlist
These checks are simple, and they catch errors that look perfectly reasonable when the netlist is read as text. They matter even more when a netlist is drafted by hand or by an AI assistant.
- Every pin appears on at most one net. A pin on two nets is a short.
- No net has only one pin, unless that pin is meant to be a test point.
- Power and ground nets reach every supply pin of every IC.
- Pin numbers match the footprint, so the layout connects the pads you think it does.
IPC-D-356 and bare-board testing
Fabs can electrically test bare boards against a netlist in IPC-D-356 format. The tester checks that every net is continuous and that no two nets are shorted, catching manufacturing defects before assembly.
Work it out with a free tool
From one sentence to a netlist, then a board
Text to PCB turns a plain-language request into a netlist, places and routes it, and lets you read and edit the schematic in between.
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