The Superconductive Circuit Board

    Understanding PCB Manufacturing: Impedance Control

    Printed circuit boards with impedance requirements demand a high level of precision.

    Image courtesy of Zmetrix

    For standard circuit boards, a PCB manufacturer is given a set of patterns - copper patterns, hole patterns, ink patterns, which are combined into a single circuit board with all the pattern sizes and positions within certain tolerances. Failure to meet a certain size or position with the specified tolerance can be cause for the circuit board to be rejected. If a trace has been defined as an impedance control trace, it is not the trace size which is strictly defined, but rather the impedance. While a nominal trace size will be provided in the Gerber layer, it is understood the circuit board manufacturer can vary trace width, height, and dielectric thickness as long as the final impedance is within tolerance.

    Is there a need for team building in Printed Circuit Board shops?

    Offsite team building events have always struck fear into my heart. It seems no-one votes for events I enjoy like ice hockey or rugby or full contact Frisbee golf.

    The normal process requires the group to solicit activity ideas which, after weeks of debating submissions like hot air ballooning, they are unable to get agreement on, a small clique must then take over and just do it. To-date I have survived:

    A view of Asian competition to the West Coast PCB Industry

    A West Coast View on Asian Competition in the PCB Industry

    At a recent Eptech High-Tech show held in Vancouver, I made a point of seeking out the PCB manufacturers, who were mostly from Ontario, and asked each of them two simple questions: what makes your shop special and if I were a customer, why would I buy from you? The answers repeated over and over, mostly with deadpan seriousness, surprised me. We’ve been in business since 1972 or 1982 or 1968, we have good customer service, we can turn a job around in 5 to 10 days. In an age where I would expect firms to be using core competencies to distance themselves from the competition, I instead found a herd mentality, like wildebeest, waiting for circling Asian manufacturers to pick off anyone who strayed from the herd.