Caps in coupling and DC blocking appCIRCUIT DESIGNER’S NOTEBOOK Capacitors in Coupling and DC Blocking Applications Capacitors used in coupling and dc blocking applications serve to couple RF energy from one part of a circuit to another and are implemented as series elements. Proper selection of coupling capacitors insures the maximum transfer of RF energy. All capacitors will block dc by definition; however, considerations for satisfying the requirements of a coupling application depend on various frequency-dependent parameters that must be taken into account beforehand. Figure 1 illustrates two RF amplifier stages operating in a 50-ohm network interconnected by coupling capacitor C 0. Table 1 outlines several device options for achieving interstage coupling at various wireless frequencies. Electrical parameters such as ser……