Saturn PCB Design, Inc. PCB design, PCB Layout, RF electronic engineering and high speed digital design. Engineering Calculators for both mechanical and PCB design, and engineeringrelated conversion calculators. Active calculator for microstrip transmission line using a formula quoted by Rick Hartley giving characteristic impedance and effective dielectric constant, with. Looking for quickturn prototype PCB manufacturing assembly of high quality Sierra Circuits is onestop shop for design, fabrication assembly of PCBs. Pcb Impedance Calculator' title='Pcb Impedance Calculator' />Comments 1. Administrator January 31, 2006 Trace Width Calculator FAQs. Raccolta Foto Windows Vista Aggiornamento Server here. Word Artist 1.2 Portable. QUESTION Very cool PCB width tool I would like to know its limits though. Zterm.JPG' alt='Pcb Impedance Calculator' title='Pcb Impedance Calculator' />Impedance Control PCB Design Manufacturing Click Hereto see our Controlled Impedance Best Price Guarantee FREE Shipping Impedance is the sum of the resistance and reactance of an electrical circuit expressed in Ohms. The resistance being the opposition to current flow present in all materials. The reactance is the opposition to current flow resulting from the effect of the inherent capacitance and inductance of the conductor interacting with changes in voltage and current. In DC circuits there is no reactance and the resistance of copper conductors is typically insignificant. However in high speed AC circuits those with sharp changes in voltage andor current the reactance and thus the impedance can become very significant. This can become critical to a designs functionality because of the effects that changes in the impedance along the signals path from transmitter to receiver will have on the efficiency of power transfer as well as signal integrity. While a circuits speed is often expressed as the frequency of the wave form the critical concern is the speed at which the voltage andor current is required to change. The typical design considerations involved in the determination of the requirement for controlling the impedance are the strength of the signals involved, the susceptibility of the circuit to noise and signal distortion, the criticality of signal timing and the speed at which the signals source is attempting to force a change in voltage andor current. The design considerations for setting the value of the impedance for the conductor is typically the output impedance of the transmitter and the input impedance of the receiver. The impedance of other conductors i. The acceptable range tolerance for the impedance will need to be determined and taken into account during the design phase as well as when specifying the PCB parameters. In many cases merely by using software models to determine the anticipated impedance with particular dielectric materials and spacing, followed by requesting these parameters be followed when the PCBs are fabricated will suffice. This is what we call controlled dielectric. For more critical applications you will need to specify controlled impedance and supply the actual impedance requirements for the conductors and we will fine tune the dielectrics and conductors to meet these requirements. The impedance requirements will have to be specified based on the layer and the conductor widths.