1. Introduction to Capacitors Electronics 1 CVHS

2. Terms  Capacitance - the ability to store energy in the form of an electric charge  Capacitor - a device designed to hold capacitance

3. Details  Base Unit - Farad Typically measured in micro-farads Symbol:  F (1/1,000,000th of a Farad) Also can be in pico-Farads (1/1,000,000,000,000) of a Farad  Also have a working voltage rating WVDC Similar to resistor power rating  Capacitors are not heat sensitive

4. How a Capacitor Works  A capacitor is two conductors (plates) separated by an insulator (dielectric)  A capacitor stores energy when it is connected to a voltage source (such as a battery).  Current flows until the capacitor becomes charged to the same voltage as the source.

5. Simple Capacitor

6. Discharging a Capacitor  Capacitor has the ability to discharge immediately  Battery discharges over time  Short leads of capacitors before working with them  Use a resistor to slowly discharge a capacitor so it is not damaged  Danger of Electrical Shock

7. Factors Affecting Capacitance  Plate area  Distance between plates  Dielectric material

8. Schematic Symbols  Non-electrolytic capacitor  Electrolytic capacitor has polarity dielectric soaked in electrolyte Never install backwards  Variable capacitor plate surface area can be adjusted

9. Types of Capacitors  Non-electrolytic  Ceramic Disc  Dipped Mica  Paper (molded)

10. Types of Capacitors  Electrolytic  Axial Lead  Radial Lead

11. Types of Capacitors  Variable

12. Capacitance Code NOTE: Value is in pico-farads!

13. Practice First Digit Second Digit Third Digit Letter 104K104K 100,000 pF or.1 µF ± 10% 582F582F 5,800 pF or.0058 µF ± 1% 243G243G 24,000 pF or.024 µF ± 2%

14. Review  Capacitance vs. Capacitor  Unit of Measure & Ratings  How Does it Work?  Working Considerations  What affects Capacitance  Three Types of Capacitors  Capacitance Code