Radio frequency thermal requirements

When the PCB is thermally saturated and the component temperatures are still too high to be tolerated at the maximum obtainable system air velocity, other means of conducting heat from the PCB to even larger area system structures are required. The chassis of the system is often the largest surface area structure in the system, is exposed to the ambient air, and often makes a good sink for heat that cannot be dissipated by the PCB alone. Mechanisms to conduct heat into the chassis include chassis screws, gap fillers, connectors, and side rails. Sometimes, radio frequency (RF) shields that are appropriately connected to components can provide additional heat sinking. 

The measurement of pg requires a pressure transducer system that is not influenced by the electric power used for the plasma polymerization, particularly when a high-frequency radio frequeny power is employed. Some pressure transducers that give pressure readouts independent of the nature of a gas are ideally suited for plasma polymerization. Some electronic gauges the readout of which depends on the nature of the gas (e.g., thermal conductivity) do not provide accurate readings of Pg because in most cases the composition the gas mixture in the LCVD reactor is unknown and there is no way to calibrate the meter for an unknown gas mixture. 

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