| 摘要 |
A printed circuit board (PCB) has an internal capacitor (26) with at least two conductive foils (28, 30) and one intermediate dielectric sheet (36A), the dielectric sheet including spacer material (37A) extending therethrough for uniformly maintaining its thickness and dielectric material (37B) developing a uniform dielectric constant therein, the spacer material and dielectric material maintaining the uniform thickness and uniform dielectric constant of the internal capacitor during final lamination of formation of the PCB. The internal capacitor may depend upon borrowed capacitance with the total effective capacitance of the internal capacitor being less than the combined capacitive requirements of devices coupled with the internal capacitor. In one embodiment, at least a portion of the internal capacitor is formed simultaneously with final formation of the PCB by an in situ method. In another embodiment, the internal capacitor is formed with multiple capacitor elements, at least one conductive foils in the internal capacitor forming a portion of two different capacitor elements, the number of dielectric sheets in the internal capacitor equaling the number of capacitor elements, the number of conductive foils in the internal capacitor equalling the number of capacitor elements plus one. |
