Controlled Impedance


Controlled Impedance maintains specified tolerance in the characteristic impedance of an interconnect (transmission) line used for connecting different devices on a circuit.


PCB Designers utilize controlled impedance for high-speed digital and high-frequency analog circuits. Our customers span the following industries:

  • MWRF
  • Telecom
  • DUT Chips

Common Issues

SFS provides solutions for design and final product verification, puddling and more. Standard impedance tolerances are within 10%. However, our engineering team routinely produces Controlled Impedance PCBs to hold 5% impedance tolerance. SFS achieves this by maintaining a database of past stackups and resulting thicknesses allowing our front end engineers to run tight impedance calculations. Further, numerous in-process checks are made to insure that fabrication results are as close to the designed values as possible.

Sample Boards

Impedance RF
Mouse over pictures below to see description