Pin Header
Provides multiple parallel electrical paths between a PCB and a mating connector. No active electronics — a header is just precision-spaced pins and plastic body.
A polymer body holds gold- or tin-plated brass pins at a fixed pitch. The pins solder through-hole or surface-mount to the PCB. Mating sockets clip over and make contact via spring fingers inside.
In plain terms
A row of metal teeth on the PCB that grip a matching female socket — the breadboard rail of the hardware world.
Why designers use it
- Module breakouts (Pi GPIO, Arduino headers, ESP32 dev kits).
- Programming/debug ports (JTAG, SWD, UART) on prototype boards.
- Internal cable assemblies in PCs (USB, audio front panel).
- Battery / fan / sensor pigtails on consumer hardware.
Best for
- Prototyping
- Debug ports
- Module breakouts
Key specifications
- Operating limits: Check the exact manufacturer's datasheet (A family name does not establish voltage, current, temperature or timing limits.)
- Pin assignment: Match the complete part and package code (A similar name or function does not guarantee the same wiring.)
- Mechanical fit: Use the exact package drawing (Check pad layout, dimensions and viewing direction before building.)
When not to use it
- High-vibration / high-cycle applications — locking connectors (JST, Molex Mini-Fit) are more robust.
- Currents above 3 A per pin — header pins overheat.
Common mistakes
- Plugging a 0.1" socket into a 2 mm header (or vice-versa) — pitches look similar, but one is 2.54 mm.
- Soldering a header crooked and stressing the joints when a board is plugged in.
Where you will find it
- Raspberry Pi 40-pin GPIO header is the canonical 0.1" 2×20 example.
- Arduino Uno's 'shield' header pattern has been the de-facto module-stacking standard since 2005.
- Internal motherboard front-panel headers (USB, audio, power LED) are 0.1" pitch.
A short history
0.1" pitch (2.54 mm) descends from early IBM/DEC card edge and discrete-component pitches; it was standardised in the 1960s–70s as DIP-IC and breadboard pin spacing. The Berg / Amphenol / TE family of 0.1" headers has been continuously produced since then.