Electronics: An Online Guide for Beginners

Back || Resistors | Capacitors | Diodes | Transistors | Integrated circuits |Switches

Capacitors are the second most commonly used component in electronics. They can be thought of as tiny rechargable batteries -- Capacitors can be charged and discharged. The amount of charge that a capacitor can hold is measured in Farads or the letter F. However, 1F is too large for capacitors, so microfarads(湩) and picofarads(pF) are used. micro = 1/1,000,000 and pico = 1/1,000,000,000,000

So 100,000pF = 0.1湩 = 0.0000001F

We will only be discussing two types of the most commonly used capacitors: Ceramic and Electrolytic.

Ceramic capacitors are brown and has a disc shape. These capacitors are non-polarized, meaning that you can connect them in any way. To find the value, you simply decode the 3 digit number on the surface of the capacitor. The coding is just like the resistor color codes except that they used numbers instead of colors. The first 2 digit are the significant figures and the third digit is the multiplier. These capacitors are measured in pF.
Electrolytic Capacitors has a cylinder shape. These capacitors are polarized so you must connect the negative side in the right place. The value of the resistor as well as the negative side is clearly printed on the capacitor. These capacitors are measured in 湩.