Definition

Stackup defines the layer arrangement in a multilayer PCB: the sequence of signal, ground, and power layers; the materials (core and prepreg types); dielectric thicknesses; and copper weights. A well-designed stackup ensures impedance control, minimizes crosstalk, provides adequate power distribution, and meets mechanical requirements. Symmetric stackups (mirrored around the center) minimize warpage. The stackup must be manufacturable with standard material combinations and validated for the target impedances.