Resolving Host Enclosure Resonances and Spurious Discrepancies in Embedded Radios
Resolving host enclosure resonances relies on identifying cavity modes and sealing seam apertures before submitting embedded radios for regulatory scans.
Land-Grid Array Module
Meaning
Integrated circuit packaging format that uses a series of pads instead of pins to create electrical connections with a substrate. A land-grid array module is pressed against a socket or soldered directly to a printed circuit board. The design allows for a higher density of connections within a smaller physical footprint than traditional pin based packages.
Assembly Process
Reliability of the electrical connection depends on the precise application of solder paste and the accuracy of the pick and place machine. The land-grid array module requires a specific reflow profile to ensure that all pads wet correctly and form stable joints. In socketed versions, a retention mechanism provides the necessary force to maintain contact across the entire grid.
Inspection of the hidden joints is typically performed using X-ray equipment to verify the integrity of the bond.
Electrical Signal
Impedance control is improved because the signal paths are shorter and more direct than those in leaded components. A land-grid array module exhibits lower parasitic inductance, which is beneficial for high speed digital and radio frequency applications. Proper grounding of the center pads is often required for thermal dissipation and electrical stability.
Thermal Transfer
Transfer of heat away from the silicon occurs through the thermal pads on the bottom of the land-grid array module. The circuit board acts as a heat sink, pulling energy away from the component and spreading it across the copper layers. Vias are often placed directly under the module to move heat to the opposite side of the board.