The complete range

Rigid-flex technology combined with impedance testing

The high clock rates of modern components and the associated short switching times for high signal transmission rates have created a requirement for impedance matching for rigid-flex technology. Not only the impedance calculation but also the documentation and measurement of impedances play an increasingly important role.

When calculating the impedances in rigid-flex printed circuit boards, the rigid and the flexible area must be considered separately. The cause of this is the differing signal behavior due to the surrounding materials. Würth Elektronik uses a special software that calculates everything one step. The results for all calculated impedance models, together with the underlying design and material parameters can be very clearly seen. This provides a significant benefit in project documentation and creation of the PCB specification.

Flex-rigid test coupons specially developed by Würth Elektronik

Furthermore, the new software has the ability to take into account the crosshatching on the reference copper layer. Crosshatching, in conjunction with the rigid-flex technology, provide several important advantages. Alongside an increase of the impedance values using the same dielectric separation, the bending behavior, especially under dynamic loading, is improved. In addition, moisture over copper pads can escape more easily during the drying process before soldering. By using test coupons specially developed by Würth Elektronik, impedances in the flex area are measured. Through this, a complete monitoring of the signal behavior from transmitter to receiver is possible. This specific rigid-flex measurement coupons are integrated into the manufacturing panel or delivery panel. The impedance is then measured and logged before delivery to the customer.