Land Pattern for 0201 Components on 0.8 mm Pitch Array
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solutions for decoupling finer pitch Ball Grid Array (BGA) devices, such as those with 0.80 mm pitch, are limited by land placement restrictions, preventing the effective placement of decoupling capacitors between adjacent BGA pins in both grid directions, which hinders increased design density and component miniaturization.
Innovation Solution
The design involves an electronic circuit board with a BGA grid pattern on one side and through-hole vias extending to the opposite side, where via pads are extended to accommodate two-port components like decoupling capacitors, with a solder mask having apertures over these pads for direct mounting, allowing for alignment in various directions (horizontal, vertical, or diagonal) to enhance placement flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If octagonal land patterns with specifically filled vias are used for decoupling applications, then decoupling capability is improved, but land placement is limited to between adjacent BGA pins on a grid having a 1.00 mm pitch in at least one grid direction
Solution Approach 1:
The via structure is segmented into multiple components: a via hole through the substrate, a via pad surrounding the via hole, and an extension portion that protrudes from the via pad. This segmentation allows the decoupling capacitor to be positioned relative to the via rather than constrained to specific land patterns between BGA pins, enabling placement on sub-1.00 mm pitch grids while maintaining decoupling effectiveness.
2Reliability
If decoupling capacitors are placed on opposite side of circuit card within via grid, then decoupling effect is achieved, but placement options are restricted by via and contact grid pattern
Solution Approach 1:
The invention adds a dimensional element by extending the via pad beyond the via hole perimeter. This extension creates additional placement flexibility in the lateral dimension, allowing decoupling capacitors to be positioned adjacent to vias rather than requiring specific relationships to BGA pins. The extension portion provides extra soldering area and enables placement on finer pitch grids while maintaining the decoupling benefit of positioning capacitors near their associated vias.
Data Source
AI summary
A land pattern for 1 mm and 0.8 mm pitch arrays has been disclosed for placing two port devices. The land pattern includes a ball grid array (BGA) of BGA pads each connected to a respective through hole via, and a pair of rectangular conductive pads electrically connected to a an adjacent pair of through hole vias, wherein each rectangular pad extends out from its via towards the other via of the pair along a line connecting the centers of said adjacent pair vias. A solder mask is located on the rectangular pad side and has apertures over each rectangular conductive pad. The land pattern is particularly useful for locating two port devices directly underneath a BGA device while minimizing the distance from a BGA ball to the two port device lead.