With the continuous shrinkage of the minimum feature sizes of semiconductor integrated circuits and their packages along with the increase in the operating frequency have caused parasitic electromagnetic (EM) coupling to become a serious design concern. Realizing the significant role of EM coupling in influencing the system and device-level radio frequency (RF) performance entails a good understanding of the coupling mechanism occurring in a certain EM environment. EM coupling between the circuit elements can be considered as a desirable or undesirable phenomenon depending upon the intended application, the intrinsic EM structure, and components forming the RF circuit. EM coupling is necessary for the design of coupled microwave structures such as coupled line filters, couplers, microwave baluns, and several other distributed circuits. In other cases, however, EM coupling is not beneficial and considered as a source of EM interference (EMI) that can drastically impact the electrical performance of the circuit.

Chapter Contents:

• 5.1 Introduction
• 5.2 Electromagnetic coupling types
• 5.2.1 Inductive coupling
• 5.2.2 Capacitive coupling
• 5.2.3 Mixed coupling
• 5.2.4 Common path coupling
• 5.3 Coupled transmission lines
• 5.3.1 Single transmission line
• 5.3.2 Symmetric coupled transmission lines
• 5.3.2.1 Common and differential mode impedance
• 5.3.2.2 Even-and odd-mode impedance
• 5.3.3 Asymmetrical coupled transmission lines
• 5.3.3.1 Approximate normal-mode parameters
• 5.3.4 Additivity of electric and magnetic coupling
• 5.4 EM fields and shielding
• 5.4.1 Electromagnetic field boundary conditions
• 5.4.2 Near-, transition-, and far-field regions
• 5.4.3 Electromagnetic shielding
• 5.4.4 Interconnects shielding by via fence
• 5.5 Anisotropic laminate materials
• 5.6 PCB and laminate design considerations
• References

Inspec keywords: monolithic integrated circuits; electronics packaging; radiofrequency integrated circuits; electromagnetic coupling

Other keywords: coupled microwave structures; anisotropic laminate materials; circuit elements; design concern; coupled transmission lines; receive RF paths; system paralysis; EM shielding; electromagnetic field couplings; transceiver modules; EM interference; approximate normal-mode parameters; couplers; transmit RF paths; coupled line filters; operating frequency; microwave baluns; radio frequency performance; distributed circuits; electrical performance; circuits packages; PCB design; RF circuit; laminate design; cross-isolation issues; semiconductor integrated circuits

Subjects: Semiconductor integrated circuits; Electromagnetic compatibility and interference; Product packaging; Microwave integrated circuits