Appendix D. Units and Prefixes

Units

Table D-1 lists the most common units used in electronics along with the typical ranges of those units you might find in practice.

Table D-1. Common Units and their Typical Ranges of Values
Property Unit Typical range
Current A (Ampere) 100nA to 100A
Voltage V (Volt) 1mV to 1000V
Resistance Ω (Ohm) 10mΩ to 20MΩ
Energy J (Joule) 1J to 1MJ
Watt W (Watt) 1mW to 10kW
Capacitance F (Farad) 10pF to 10F
Inductance H (Henry)  
Frequency Hz (Hertz)

sound 20Hz to 20kHz

radio 3kHz to 300GHz

Unit Prefixes

Table D-2 shows the unit prefixes applied to electronic and other units. You will sometimes find R used in place of Ω and u in place of µ.

Table D-2. Unit Prefixes
Prefix Multiplier Scientific
p (pico) 1/1,000,000,000,000 10E-12
n (nano) 1/1,000,000,000 10E-9
µ (micro) 1/1,000,000 10E-6
m (milli) 1/1,000 10E-3
k (kilo) 1,000 10E3
M (mega) 1,000,000 10E6
G (giga) 1,000,000,000 10E9