leds for beginners

by:CTECHi     2019-12-25
This Instructure shows how to connect one or more led in a basically clear way.
Have never done any work on LEDs before and have no idea how to use them?
It\'s okay. I\'m not.
* This explanation may seem too simple if you have connected LEDs before.
Think about yourself.
So I\'m not completely honest.
I used LEDs once or twice in a simple application before, but I never knew what I was doing because many of the projects on instructures use LEDs, I think I can also teach myself and post.
I know that many projects have been released with information on how to connect LEDs for simple projects --
LED beginner\'s project: LED flashlight for Part 2 and Part 9 v-
Best evarrr!
, But I think for anyone who can use the led, a detailed step-by-step explanation is still of some use.
The first step is to buy some supplies and find out what I need to try.
For this project, I ended up going to Radioshack because it was very close and it was accessible to a lot of people --
But it should be noted that the price of this kind of thing is really high, there are various low-cost places on the Internet to buy LEDs.
To light up an LED, you need at least the LED itself and the power supply.
From what I have read from other LED instructions, wiring in resistors is almost always a good idea.
If you would like to know the Wikipedia entry that these materials have been checked out: LEDsPower supplies materials: LED lights,
I basically just put my hand in the drawer of the radiosack and took out something that didn\'t exceed $1 or $2 per LED.
I got: 2760307 5mm red LED 1.
Month V276035 January mm yellow LED month.
1 V2760036 flashing light red LED 5 V2760041 2 packaged red LED 2.
6 V2760086 giant red LED 2. 4 v power supply-
I really don\'t know what I need to power them, so I bought some 9 v batteries and some 1. 5V AA\'s.
I think this will allow me to mix and match and make enough different voltage combinations to light something up
Or at least burn those little idiots in a bad plastic smoke. Resistors -
Again, I\'m not quite sure what I need in terms of resistance here.
Since I have a bunch of LEDs with different voltages, I know I need a couple of different types of resistors, so I just bought a pack of carbon film resistors with 1/2 Watts (2710306).
I also collected a welding gun, solder, needle and nose pliers, pliers, some primary wires and electrical tape because I thought they might be useful.
The LEDs have different sizes, brightness, voltage, color and beam mode, but the choice of radiosack is small, so I picked up a few LEDs that are different from them at several different brightness and voltage.
I keep a close track of what voltage the LED is because I don\'t want to accidentally send too much current through a low voltage LED.
The first thing I do with the led is to find out which wire (
Called electrode)
It\'s positive. it\'s negative.
In general, the longer line is the positive pole, and the shorter line is the negative pole.
You can also look at the LED itself and see what\'s going on.
The smaller piece of metal inside the LED is connected to the positive pole, and the larger piece of metal is connected to the negative pole (
See below).
But be warned -
In the LEDs I picked up, I don\'t always find this to be true, and some LEDs have longer negative poles when it should be on the positive. Go figure -
It doesn\'t matter though. if it doesn\'t light up, I\'ll flip it over.
Once I know what is positive and what is negative, I have to remember what the voltage is for each LED.
All my LEDs recommend 20 mA current.
20 mA is the standard for most LEDs.
To make the power supply, I just welded some wires at both ends of the battery I bought so that I could easily connect the LEDs to them.
9 v battery as my 9 v power supply, one AA battery made a 1.
5 V power supply and 3 AA batteries are bundled together to make 4 knots. 5V (1. 5V + 1. 5V + 1. 5V = 4. 5V)power supply.
I didn\'t use crocodile clips at the end of the wire, but here they will help.
I opened the category pack and found that the resistors were not marked with their values.
The package says it contains a whole bunch of different resistors from 100 ohms to 1 Mbps, so I\'m starting to see what it is.
When I was browsing online, I found a coding system on all resistors telling you the value of them.
Here are two pages explaining in depth how to calculate the value of the resistor.
Do it yourself, do it for you. I will be in the next few steps, examples of calculating the values myself when I start wiring my led.
At the moment, I just appreciate their little colored stripes and go ahead and try to get an LED to light up.
I think I will start as simple as I can
There is only one LED with no resistance.
First of all, I have to decide what power supply to use and which LED to light up.
This seems obvious, but this is my first pass, so I might as well be as clear as I can. . .
LEDs need enough voltage to light them up.
Sometimes, if the voltage you give them is too low, they don\'t shine at all, and other times they glow dimly with low voltage.
High voltage is not good, will burn out the LED in an instant.
So ideally you want the voltage of the LED to match your supply voltage, even a little lower.
To do this, you can do something: change the voltage of your power supply, change the LED you use, or, you can use the resistor, this resistor allows you to use a higher power supply with a lower voltage.
Now I just want to light up one, so I chose the lowest voltage power supply
Single AA battery with output 1. 5V.
I chose to light up red 1.
1, 7 v led due to battery output.
I know I won\'t kill the LED with too much energy.
I wrap my positive pole from the battery to the positive pole of the LED and wrap the negative pole from the battery to my negative pole and then prepare-
Let the LED lights light up!
The first experiment is easy to do.
Just some wire twist and enough knowledge to know 1.
5 V power supply will light up 1.
7 v LED with no resistance required.
I bought a 1 LED and it was just a coincidence.
7 v, it was finally able to power my 1.
5 v power supply without resistor.
For the second setting, I decided to use the same LED, but increased my power supply to three AA batteries that are connected together and output 4. 5V -
Enough energy to drain my 1.
7 v led so I have to use the resistor.
I used the formula to figure out which resistor to use: R = (V1 -V2)
/Iwhere: V1 = supply voltage 2 = LED voltage = LED current (
Usually 20 mA. 02A)
Now there are many calculators on the Internet that can help you with this.
However, many other instructures think this is a good example, and math is not too hard, so I want to do the calculations myself to find out what is going on.
Again, my LED is 1.
7 V, 20 mA required (which is . 02 A)
Currently and my supply is 4. 5V.
So the math is. . . R = (4. 5V -1. 7V)/ .
02 AR = 140 ohmsOnce I know I need a resistance of 140 ohms to get the right amount of voltage for the LED, I looked at my resistor classification package to see if I could find the right one.
Knowing the value of the resistor requires reading the code from the ribbon of the resistor itself.
This package does not have a resistance of 140 ohms, but it does have a resistance of 150 ohms.
It is always better to use the next nearest value resistor that is larger than you calculated.
Using a lower value can burn out your LED.
To figure out the color code, you basically break down the first two digits of the resistor value, multiply the previous two digits using the third digit, and then specify the fourth digit as a tolerance indicator.
This sounds much more difficult than it actually is.
Number the secret decoder website using the color found here, a resistance of 15 ohms should have the following color code. . .
Brown, because the first number in the value resistor I need is 1 Green, because the fifth number is 5 Brown, because in order to reach 150, you have to add a 0 to 15 to reach 150. Gold -
The resistors I get all have a tolerance of 5%, and if it doesn\'t make sense, 5% is represented by the decoder page link above goldCheck out.
I went through all the resistors and found that brown, green, brown, Golden resistor and wired on the positive pole of the LED. (
Whenever a resistor is used on the LED, it should be placed before the LED on the positive pole).
Low, look, the LED lights up again.
The resistance of 150 ohms stopped enough 4.
5 v power supply from 1.
The 7 v led makes it light safely to prevent it from burning out.
This is just a process I go through and I want to know what resistors to use in my specific LED and in my specific power supply.
You can easily use the formula above to calculate what value resistors you happen to use for any LED and power supply.
Now that I know how to connect an LED with a variety of LED voltage and power combinations, it\'s time to explore how to light up multiple LEDs.
There are two options when it comes to connecting more than one LED to the power supply.
The first option is the series wiring, and the second option is the parallel wiring.
To see an in-depth explanation of the differences between tandem and parallel lines, check this page.
I will introduce Series LEDs first.
End-to-end connection of led connected in series (
The negative pole of the first LED is connected to the positive pole of the second LED, the negative pole of the second LED is connected to the positive pole of the third LED, and so on. . . ).
The main advantage of the series wiring is that it distributes the total voltage of the power supply between all LEDs.
This means that if I have a 12 V car battery, I can power 4, 3 V LEDs (
Connect a resistor on each resistor).
Assuming this can also power 12, 1 v LEDs; 6, 2V LEDs;
If something like this exists, even 1 12 v LED.
Okay, let\'s try line 2.
A 6 v LEDs in series with a 9 v power supply and through mathematical calculations. R = (9V -5. 2V)/ .
02AR = 190 OhmsNext high resistance value-
The various packages of 200 OhmsNow resistors are not equipped with a resistance of 190 or 200 ohms, but it does come with other resistors that I can use to make a resistance of 200 ohms.
Like LEDs, resistors can be connected in series or in parallel (
For an explanation of things connected in parallel, see next).
When the same value resistors are connected in series, you increase their resistance.
When the same value resistor is connected in parallel, you divide the value of the resistor by the number of resistors connected together.
Therefore, in the simplest sense, the resistance of the two 100 ohms connected in series will be equal to the resistance of 1 200 ohms (100 100 = 200).
The two 100 ohm resistors in parallel are equal to one 50 ohm resistor (100 / 2 = 50).
Unfortunately, I learned this after I connected the resistors together for the experiment.
I originally wanted to connect two 100 ohm resistors together to equal the 200 ohm resistor needed to protect the led.
Instead of concatenating them as it should be, I connect my resistors in parallel (
Did I mention that I am a beginner in resistors? )
So my resistance only provides a resistance of 50 ohms.
Obviously, my LEDs work fine for a short period of time in the experiment.
In the long run, there is too much power going into LEDs that could run out of them. (
Thanks to beanwaur and shark500 for pointing this out. )
I took my resistors and put them in front of the positive pole of the first LED in series and attached them to the battery and LED lights again!
There are three different combinations of Led and battery power supply, no plastic smoke but looks good
In addition to my little confusion between the series resistor and the parallel resistor.
Unlike the series led, the connected led uses a wire to connect all the positive poles of the led you use to the positive pole of the power supply, and use another wire to connect all the negative poles of the led you use for the negative poles of the power supply.
Parallel wiring has some obvious advantages over series wiring.
If you connect a bunch of LEDs in parallel instead of separating the power supply provided to them, they will all be shared.
Therefore, a 12 v battery connected in series to Four 3 v LEDs will assign 3 v to each LEDs.
However, the same 12 v battery in parallel with four 3 v LEDs will provide a complete 12 v for each LED-
Burn the LEDs for sure!
Parallel wiring led allows many LEDs to share a low voltage power supply.
We can put the same four 3 v LEDs in parallel to a smaller power supply, for example, two AA batteries have a total of 3 v, each LEDs will get the 3 v they need.
In short, the series wiring separates the total power supply between the LEDs.
Connecting them in parallel means that each LED will receive the total voltage output from the power supply.
Finally, just a few warnings. . .
Parallel wiring consumes your power supply faster than tandem wiring, as they end up drawing more current from the power supply.
It only works if all the LEDs you use have the exact same power specifications.
Do not mix and match led of different types/colors when wiring in parallel.
Okay, start doing it now.
I decided to do two different parallel settings.
The first one I tried was as simple as possible-just two 1.
7 v LEDs in parallel with a single 1. 5V AA battery.
I connect the two positive poles on the LEDs to the positive from the battery and connect the two negative poles on the LEDs to the negative poles from the battery. The 1.
Because no resistance is required for 1,7 v LEDs.
5 v from the battery is enough to light the LED, but not more than the LED voltage-
So there is no risk of burning it. (
There is no picture for this setting)Both of the 1.
The 7 V LEDs are lit by 1.
5 v power supplies, but keep in mind that they drain more current from the battery, making the battery consume faster.
If there are more LEDs connected to the battery, they draw more current from the battery and run out of current faster.
In the second setup, I decided to put everything I learned together and connect the two LEDs in parallel to my 9 v power supply --
There must be too much juice for LEDs, so I have to use resistors.
To figure out what value I should use, I went back to the trusted formula --
But since they are connected in parallel, the formula changes slightly in terms of currentI. R = (V1 -V2)
/Iwhere: V1 = supply voltage 2 = LED voltage = LED current (
We use 20 mA all the time in other calculations, but since the LED in parallel wiring absorbs more current, I have to multiply the current absorbed by one LED by the total number of led I use.
20 mA x 2 = 40 mA, or. 04A.
The value of my formula this time is: R = (9V -1. 7V)/ . 04AR = 182.
5 OhmsAgain, since the variety pack is not equipped with a precise value resistor, I am trying to make a resistance of 100 ohms using two 200 ohm resistors in series.
I ended up repeating the mistakes I made at the last step, though, by mistake putting them in parallel, so the two 100 ohm resistors ended up providing only 50 ohm resistors.
Again, these LEDs are particularly tolerant of my mistakes --
Now, I have learned valuable lessons about series-parallel resistors.
Last Note on parallel wiring led
When I put my resistor in front of two LEDs, it is recommended that you put a resistor in front of each LED.
This is a safer and better way to connect LEDs in parallel with resistors
And make sure you don\'t make mistakes that I accidentally made. The 1.
7 v LEDs connected to a 9 v battery light up-
My little adventure on LED land was completed.
While I didn\'t actually make anything other than a few LEDs, this information can be used to make all kinds of cool stuff!
The concept of hope to take away is :-
Power a bunch of led with different values using the same rationale. -
Through observation and testing, find out what is the positive pole and what is the negative pole of the LED. -
Use a resistor or resistor combination in series or in parallel to provide the right power for the LED. -
Calculate using a formula or using a website to determine what resistance is needed. -
Series or parallel wire LEDs depending on the application. -
Let the led light up!
This is the most basic way to walk possible led
I learned a lot along the way.
LED arrays and cabling solutions can become more complex
But for the most part, LEDs work very simply, and I can light them up with relatively little knowledge --
If I send too much juice through them at the end of the experiment, that\'s fine.
I\'m not afraid of LED now.
They\'re my friends.
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