##### Circuit Analysis For Dummies

At the most basic level, analyzing circuits involves calculating the current and voltage for a particular device. That’s where device and connection equations come in. Device equations describe the relationship between voltage and current for a specific device. One of the most important device equations is Ohm’s law, which relates current (I) and voltage (V) using resistance (R), where R is a constant: V = IR or I = V/R or R = V/I.

The two connection equations you need to know are Kirchhoff’s current law (KCL) and Kirchhoff’s voltage law (KVL):

• Kirchhoff’s current law: Sum of incoming currents = Sum of outgoing currents at a node

• Kirchhoff’s voltage law: Sum of voltage rises = Sum of voltage drops around a closed loop

John M. Santiago Jr., PhD, served in the United States Air Force (USAF) for 26 years. During that time, he held a variety of leadership positions in technical program management, acquisition development, and operation research support. While assigned in Europe, he spearheaded more than 40 international scientific and engineering conferences/workshops.