Basic Components Electronics 2015
Batteries & Cells Chemical devices that provide DC voltage A cell is an electrochemical device made of 2 electrodes of different materials and an electrolyte. A battery is 2 or more cells connected
Lamps Commonly indicator lights and illumination in cars, planes, appliances, flashlights Uses tungsten filament wire to emit light when heated by electric current Indicator Lamp Illumination Lamp
LED Light-emitting diode Small, low powered and reliable Polarity of leads need to be determined before connected Needs about 1.5 V and operates on 5-40 mA of current
Resistors Most common and reliable components Major purpose is to control current and divide voltage Four categories: 1.Fixed 2.Variable 3.Adjustable 4.Tapped Resistors can vary from 1 Ω to over 100 M Ω
Resistor: Fixed Power rating indicates the power a resistor can dissipate without being destroyed, this is determined by physical size and material Squared off resistors are carbon-composition Rounded off resistors are metal-film resistors Rule of Thumb! Use a power rating twice as great as the calculated value Power Rating = Voltage 2 ÷ Resistance
Resistor: Variable Potentiometer has 3 terminals, and rotation changes resistance between the middle and end terminals Rheostat has 2 terminals, adjusts current to a specified value A potentiometer can become a rheostat by not using one of the end terminals PotentiometerRheostat
Resistor: Adjustable Similar to potentiometers and rheostats These are commonly used in high-power circuits (over 2 Watts) Only for infrequent resistance changes Not adjustable when the circuit is in operation 30 Watt 10K Ω
Resistor: Tapped Just like the adjustable resistors Commonly used in high-power circuits (over 2 Watts) Not adjustable when the circuit is in operation 70 Watt 500 Ω
Resistor: Surface Mount Surface Mount Devices or chip components They do not have leads, soldered to traces on circuit board by their terminal pads Power ratings don’t normally exceed ¼ Watt
Switches All perform the same operation, to open and close a circuit Can only exist in 2 states: Open or Closed Push Button, Rocker, Slide and Magnetic
Switch: Momentary Active if they are pressed or actuated Push buttons, joystick, keyboard PBNO = Push Button Normally Open PBNC = Push Button Normally Closed
Switch: Maintained Stays on or off until it is switched Slide—Simple on/off selector switch Toggle—Long lever with rocking motion DIP—Not commonly used in modern electronics (arcade games and video cards)
Switch: Symbols Poles—defines the #of circuits the switch can control Throw—defines the #of positions the poles can connect to
Capacitor
Bust A Cap!
References basics?_ga= #switch-applications