Patent ID: 8291370

Claim:
A surface mount circuit board, having a plurality of predetermined layout positions provided for at least one surface mounted component to be electrically disposed thereon, the circuit board comprising: a substrate, having a plurality of actual layout positions; and a plurality of pads, respectively disposed on the actual layout positions, wherein an offset distance exists between the actual layout positions and the predetermined layout positions, and the offset distance is determined according to a following equation: d =( CTEaâˆ’CTEb )Ã—( Tsâˆ’Tr ) where, d is the offset distance between the actual layout positions and the predetermined layout positions; CTEa is a coefficient of thermal expansion of the substrate; CTEb is a coefficient of thermal expansion of the surface mounted component; Ts is an operating temperature for combining the surface mounted component with the circuit board; and Tr is a room temperature.