IPC Apex Expo in late March was judged by most to be a success, with attendance showing some signs of life, and a lot of machines listed SOLD signs.
Over the past five years, laminated-based chip embedding has taken a huge step toward industrialization.
QFNs, microBGAs and 0201s keep showing up everywhere. They used to appear only on boards requiring miniaturization; now they are used on revisions of legacy products, bringing a new set of headaches for process engineers.
After visiting scores of one-story manufacturing sites, the first impression one gets when walking up to Murrietta Circuits is its size.
When key performance characteristics are critical to system performance, engineering will want to create a source control drawing in accordance with ASME Y14.24. The source control drawing will list specific supplier(s) that have been qualified to produce the product identified in the drawing. Engineering wants to use a source control drawing because the parts’ characteristics are critical to the design, and they do not want the parts procured from an uncharacterized source of supply.
PCB performance strongly depends on the laminate material’s dielectric constant (Dk) and dissipation factor (Df) related to complex dielectric constant, ε = ε’ – jε” through Dk=ε’/ε0 and Df=ε”/ ε’. Complex permittivity can be measured using a number of techniques, including waveguide, cavity resonator, open resonant cavities, split-post dielectric resonator and free-space techniques.