PCB Return-Current Distribution in a Microstrip Line

This article discusses the distribution of a PCB return current underneath top trace for the microstrip configuration. Next month’s article will discuss the distribution for the stripline configurations.

Common-Mode Current Creation and Suppression

This article discusses the creation of a common-mode current in a typical circuit and explains the effectiveness of a common-mode choke on differential-mode and common-mode currents.
1409 F2 cover

I’m Partial to Partial Inductance!

1409 F2 coverIt is well known (but often forgotten) that the concept of inductance, without defining a complete loop of current, is completely meaningless! Some books give inductance of a length or wire, some people talk about the inductance of a via, and still others talk about the inductance of ground braids, etc. All these discussions about inductance ignore the requirement for a complete loop before the total or loop inductance can be discussed in any meaningful way.

1406 TS fig1

Resistor Value for Measuring Leakage Current

Furor and controversy are words which describe the process by which standards committees decide the value of the resistor in the leakage current measuring network. However, the different specified resistor values create no more than a 6.25% error for the value of the leakage current.