Electronic Circuits with MATLAB, PSpice, and Smith Chart

Appendix GStandard Values of Resistors, Capacitors, and Inductors

G.1 Color Code of Resistors

Except for wire‐wound/cermet/high‐power/precision resistors, most common resistors do not have their resistance value printed on them, but rather have a color code representing their resistance value as illustrated in Figure G.1. Table G.1 shows the numerical value or tolerance (manufacturer’s reliability rating) represented by each color. For example, the resistance value of a resistor with the four‐color band of yellow‐violet‐red‐silver is

(G.1)

and that of a resistor with the five‐color band of orange–black–white–gold–gold is

(G.2)

• (cf.) Visit the web site http://xtronics.com/kits/rcode.htm for more details about the color code.

G.2 Standard Values of Resistors

Discrete resistors are commercially available only in standard values depending on their tolerance as listed in Table G.2. Consequently, when the designed value of a resistor is 3.1 kΩ, we should use 30×10² ± 5%[Ω] or 309×10¹ ± 1%[Ω] unless we somehow have a resistor of 3.1 kΩ fabricated.

Figure G.1 Color code for resistors. (See insert for color representation of the figure.)

Table G.1 Color code of resistors.