PCB Impedance and Capacitance of Microstrip

W		[m]	width of the trace
H		[m]	height of dielectric above return plane
T		[m]	trace thickness
Er		[ ]	relative permittivity of the dielectric
	Are there distributed capacitive loads on this trace? NoYes
La		[m]	average length of the traces attaching the loads
Ca		[pF]	average load capacitance
	OUTPUT
Z0		[Ohm]	characteristic impedance
C0		[F/m]	capacitance per unit length
tpd		[s/m]	propagation delay
L0		[H/m]	inductance per unit length
Zc		[Ohm]	effective characteristic impedance
t'pd		[s/m]	effective propagation delay

NOTE: numbers are in scientific notation (e.g.: 1.427e-9 s/m = 1.1427·10^-9 s/m = 1.427 ns/m)

CONDITIONS: ( 0.1 < W/H < 3.0);

Formulas:

Capacitive Load Modify:


See also notes on PCB Impedance and Capacitance Calculator page.