ABSTRACT
Signals and States v(t) or v time-variable entities → lower letters V time-invariable entities → capital letters I, V, Q, .. signals or states, as well as circuit component designaR, C, L tors (such as Capacitors, Inductors, etc.) and its value
assignments are denoted by italic letters, e.g. R = 10 Ω for a Resistor with 10 Ohms
Voltage Arrows in Circuit Diagrams Unfortunately, there are two standards for the designation of a voltage drop in circuit diagrams: the voltage arrow can point either in the direction of falling or rising potential. Since this can lead to major confusion, many authors avoid the problem by omitting voltage pointers altogether. Instead, they use "+" and "–" symbols to indicate polarities. However, this method is not fully satisfactory either, because this suggests that a device can only support voltage of one polarity. In this book, all voltage arrows point from the higher potential towards the lower potential, as shown in the figure below:
