Definition

Pitch is the center-to-center distance between adjacent leads or pads. Standard through-hole: 2.54mm (0.1 inch). Fine-pitch SMT: 0.5mm, 0.4mm. Ultra-fine BGA: 0.3mm, 0.25mm. Smaller pitch increases density but challenges manufacturing - finer stencil apertures, tighter placement accuracy, smaller vias for escape routing. 0.4mm BGA pitch typically requires HDI (micro-vias). Below 0.3mm pitch may need advanced packaging (interposers, embedded die). Component pitch determines PCB technology requirements and assembly capability. Verify your assembler can handle the pitch before selecting components.