01 30 56 43 80
Manufacture of controlled impedance circuits
The operating speed of electronic components increases, so does the need for controlled impedance PCBs. If the impedance is incorrect, it is difficult to identify the problem once the card is wired. Since the impedance depends on many parameters (width and thickness of the track, thickness of the laminate, etc.), FORMATRONIC tests 100% of the impedance controlled circuits. The test is not made on the printed circuit itself, but on a test coupon of the same panel and manufactured at the same time.The typical test coupon is a printed circuit that has the same characteristics and stackings as the main circuit. Its controlled impedance tracks have the same dimensions as those of the PCB and are in the same layers.The following indications will give you some idea of the connections between impedance value and dimensions, it must be remembered that these are only approximations in the case of thin tracks.
• The impedance is inversely proportional to the track width.
• The impedance is inversely proportional to the track thickness.
• The impedance is proportional to the thickness of the dielectric.
• The impedance is inversely proportional to the square root of Er of the dielectric.
For any information, do not hesitate to contact us on this number: 01 30 56 43 80, or by email to firstname.lastname@example.org. We will be happy to answer you