CONTROLLED IMPEDANCE FOR DATA INTEGRITY AND SIGNAL CLARITY

Not only are our design engineers experts in PCB routing methods and component placing that achieve our customers’ desired impedances but they can also deliver -/+ 10% tolerance, and in special cases -/+ 5%. Below are a few reasons why you should trust Sierra with even your most ambitious specifications:

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  We create a stack-up in accordance with our fab processes to guarantee zero failures.
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  We know how to route single-ended and differential pair traces to meet the targeted impedance.
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  We achieve propagation delay by designing precise length matching during the design phase.
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  We optimize the placement of components, vias, and coupling capacitors to ensure controlled impedance through assembly.

RESOLVING TRACE AND VIA STUBS

The part of a via that is not used for signal transmission is called a via stub. It acts as a resonant circuit with a specific resonant frequency at which it stores maximum energy. If the signal has a significant component at or near that frequency, that component will be heavily attenuated due to the energy demands of the via stub at its resonant frequency. To avoid the effects of via stubs on signal attenuation and data transfer rates, our electrical engineers calculate the maximum allowable via stub length where if ‘fmax’ is the maximum frequency component of a signal that needs to be faithfully transmitted, then the resonant frequency of the via stub should exceed ‘fmax’ by a good enough margin (usually 40%).

WHEN SIGNAL ATTENUATION RESULTS IN SIGNAL DEGRADATION

Conducting line resistances and dielectric material dissipation factors impact signals as they travel over traces. Our designers control these losses in high-frequency designs where components endure greater attenuation. If not properly handled, signal attenuation may lead to a diminution in signal bandwidth, causing distortion by the increase in signal rise time that is likely to generate errors in data detection.