Basic Electronics

1. Basic Electronics Part Two: Electronic Components

2. Components can be placed “in series” (i.e. one after another) so that electrical current must pass through them one after another before returning to the battery. Components in series have the same electrical current passing through them.

3. On the other hand, components can be placed “in parallel” (i.e. one beside another) so that the electrical current must chose which one component to pass through, bypassing the others. Components in parallel have the same voltage drop but usually carry different amounts of current, with more current flowing through the easiest path (i.e. the path with the least resistance).

4. Components and Vocabulary

5. Battery: pushes on the electrical charges (though none will actually flow if the circuit isn’t complete) – the battery has two terminals labeled positive (+) and negative (-) – the most negative voltage region in the circuit, often the negative end of the battery, is sometimes called “ground” or 0 volts – the amount of push the battery supplies is the “battery voltage”, often 1.5 V or 9 V or 12 V (with respect to ground) – as a battery gets worn out (or if it gets too cold!) its voltage will go down until the battery is too weak to continue to push current through the circuit symbol

6. Wire: provides a path through which electrical current can flow – ideally a wire has no resistance symbol

7. Resistor: serves as a current path but limits the amount of electrical current flow and reduces the pressure (i.e. drops the voltage) – resistance is measured in Ohms (Ω) – for resistors it doesn’t matter which way + and – are connected – when current flows through a resistor the resistor may get hot (i.e. it “dissipates” energy), so resistors can also be used as heaters symbol

8. Switch: place where a current path can be mechanically opened and closed, to start or stop the flow of electrical current – switches are used to turn things ON and OFF – place the switch in series with the component(s) it is meant to control, like a battery symbol

9. Capacitor: serves as a place to temporarily store electrical charge, like a temporary battery – “charge it up” (store electrical charge) then “discharge it” (temporarily produce electrical current) – capacitance is measured in Farads (F) – electrolytic capacitors are ones in which it matters which way + and – are connected symbol

10. Diode: serves as a one-way valve, only allowing current to flow one direction under normal circumstances – an LED (light emitting diode) is a diode (often red or green) that glows when current flows through it – diodes must be inserted the right way around for the circuit to operate correctly symbols

11. Voltage regulator: a chip that can be powered by a range of voltages but uses internal circuitry to drop the voltage to output a very stable voltage (e.g. a “5 V regulator” might be able to able to be able to run off any voltage from 6 V up to 20 V, but it always outputs exactly 5 V) – this is handy for providing a constant voltage to components even when dealing with batteries that can vary in voltage and circuits that can vary in overall resistance

12. IC (Integrated Circuit, AKA chip): a silicon chip with many tiny transistors on-board which can be programmed to make decisions (a microprocessor chip), to store digital information (a memory chip), to convert digital input to analog form (DAC), or vise versa (ADC), etc. – connects to other components through its multiple legs, called pins – be very careful never to put a chip in backward!

13. Breadboard: a board into which components can be plugged and unplugged, allowing one to build and check circuits without having to be as permanent as soldering them together

14. Transistor: 3-leg device used in logic circuits so that a small/weak electrical current at one point can control a much larger/more-powerful electrical current elsewhere in the circuit