How to Control Impedance

Characteristic Impedance 
The transmission line’s characteristic impedance depends on how the width of a conductor, the thickness of a conductor, the thickness of the dielectric between the conductor and the ground power reference planes, as well as the dielectric constant of the dielectric medium relate to one another. 

During the beginning stage of design, it is suggested that the client contact Bittele Electronics to discuss the impedance requirements. This discussion will provide a platform of communication for all parties to ensure the specifications and effects of material characteristics, including specific DKs and production processes, will have on the project’s impedance requirements and tolerances. 

To determine the real impedance may require building a small prototype in order to test it. This is usually required due to the close impedances necessary in a design. It may also be necessary when a design has small line widths and dielectric thicknesses that have greater sensitivity to changes. For instance, a tolerance change from variation in etching have more significance for a 0.125 mm (0.005 inch) line width than for a 0.25 mm (0.100 inch) line. 

Document the reference dimensions for line width and dielectric thickness only. This permits Bittele Electronics to make small changes to the line width and dielectric thickness to correspond to impedance goals. 

Note: When it is needed to make a modification of a line width, it needs to be done to all of the lines of the same width in a particular layer. The client must give permission to make this type of modification. 

Consider the importance of the Etch Factor when making impedance calculations. 

The Etch Factor is the resultant reduction of a line width during the etching process. However, it is not necessary to consider the Etch Factor for PCBs that possess an Aspect Ratio GE 4.5:1 or boards that are GE 2.3 mm (0.093 inch) thick and have an Aspect Ratio of GE 3:1. 

The suggested tolerance for impedance is +/- 10 percent. A smaller tolerance is usually attainable, particularly with complete embedded micro-strip and strip-line structures. Discuss this specification with Bittele Electronics for the best results.

When SMT matter to your business, partner with Flason. Where innovation takes form.
reflow oven lead free reflow oven LED strip reflow oven dual rail reflow oven custom reflow oven China reflow ovenSMT Peripheral Equipment SMT reflow oven 
wave soldering machine pick and place machine lead free wave soldering machine custom wave soldering machinecustom pick and place machine SMT Assembly line
SMT Reflow Oven Manufacturer Wave Soldering Mahchine Manufacturer Pick and Place Machine Manufacturer Reflow Oven Manufacturer SMT Spare Parts LED Pick and Place Machine
Andrey: sales@flason-smt.com Wechat whatsapp:+86 13691605420 

Keywords: Reflow Oven SMT Reflow Oven Wave Soldering Machine SMT Stencil Printer Pick and Place Machine SMT Inspection machine SMT Assembly Line SMT Peripheral Equipment SMT Spare Parts reflow oven lead free reflow oven LED strip reflow oven dual rail reflow oven Custom reflow oven China reflow oven SMT Peripheral Equipment SMT reflow oven wave soldering machine pick and place machine lead free wave soldering machine custom wave soldering machine custom pick and place machine SMT Assembly line SMT Reflow Oven Manufacturer Wave Soldering Mahchine Manufacturer Pick and Place Machine Manufacturer Reflow Oven Manufacturer SMT Spare Parts LED Pick and Place Machine

For More information,visit US: Reflow Oven Manufacturer or SMT Reflow Oven Wave Soldering Machine SMT Stencil Printer Pick and Place Machine SMT Inspection machine SMT Assembly Line SMT Peripheral Equipment SMT Spare Parts SMT Feeder SMT Nozzle Feeder storage cart USB Flash Drive Manufacturer wave soldering machine manufacturer Email us: sales@flason-smt.com