Dielectrics in micro-circuitry for communications

A little over a decade ago, two technologies emerged from the laboratories which were to have a profound impact on the military communications and electronics equipments of today. First, pre-fabricated wiring introduced an orderly geometrical discipline, automation of inter-connections and modular subassemblies within equipments. Secondly, the transistor permitted the design of many circuits with marked reduction in size, power requirements, operating voltages and temperature rise. Figure 1 illustrates a typical application to circuitry from a telemetry deck of one of the early “Explorer” Satellites. Here fullest use is made of printed wiring and transistors as well as special subminiature passive components scaled down for compatibility with transistor characteristics. This low power digital circuit contains solid tantalum capacitors, multilayer high K ceramic capacitors, 0.1 watt fixed resistors, and glass packaged diodes. Higher power levels and tuned circuits require the use of miniature foil capacitors and stable film resistors.