Diameter of clearance hole in the ground plane [cm]
D1
Diameter of pad surrounding via [cm]
T
Thickness of PCB [cm]
εr
Relative electric permeability of PCB material
C
Parasitic via capacitance [pF]
Consider a signal coming from back side of the board to the topside of the board
through a via. T = 0.157 cm thickness board, D1 = 0.071 cm, D2 = 0.127 cm.