Connector Selection Guide
A mismatched connector is one of the most common — and most avoidable — build mistakes. Here's how to choose the right one before you order.
Why Connector Choice Matters
Connectors need to match on three things to mate correctly: pitch (the spacing between pins), pin count, and gender. Get any one wrong and the parts simply won't connect — or worse, they'll connect incorrectly and short pins that were never meant to touch.
JST Connectors
The most common connector family in hobbyist electronics, available in several pitches that are not interchangeable: JST-PH (2.0mm), JST-XH (2.5mm), and JST-SM (2.5mm, higher current). Always check the pitch in millimeters, not just the "JST" label, before ordering a mating half.
USB Connectors
- USB-A — the familiar rectangular host-side connector
- USB-C — reversible, higher current capacity, now standard on most new devices
- Micro-USB — common on older peripherals and dev boards
Board-to-Board & Pin Headers
Standard 2.54mm (0.1") pin headers are the default for prototyping and dev boards. Finer-pitch board-to-board connectors (1.0mm, 1.25mm) show up on compact production boards where space is tight.
Avoiding Common Pitfalls
- Double-check pitch in millimeters — "JST" alone isn't a complete spec
- Confirm male/female orientation before ordering both halves
- Match the current rating to your actual load, not just the physical fit