Mixed Pressure PCB Board

A mixed-pressure PCB built by laminating different substrate materials together in a single multilayer stackup, combining high-frequency laminates (RO-series, Megtron, Aerowave) with FR-4 grades on the layers that don't need RF performance. The construction is driven by three considerations. Cost: high-frequency materials cost several times more than FR-4, so RF material is used only on RF signal layers. Reliability: blending materials with carefully matched CTE values improves z-axis reliability through thermal cycling. Electrical performance: digital, RF, and analog circuits each get the dielectric they need. The pressing process and material pairings require disciplined control of resin flow and registration. Used across 5G base stations, automotive radar, aerospace radios, defense communication, and high-speed industrial gear where one board must serve multiple signal regimes.