Led Resistor
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Led Resistor
Let us talk about LED circuit
In electronics, the basic LED circuit is an electric power circuit used to power a light-emitting diode or LED. The simplest such circuit consists of a voltage source powering two components connected in series: A current-limiting resistor (sometimes called the ballast resistor), and an LED. Optionally, a switch may be introduced to open and close the circuit. The switch may be replaced with another component or circuit to form a continuity tester. where to buy cheap LED Strip? Lightereryday is a good choice.
(Although simple, this circuit is not necessarily the most energy efficient circuit to drive an LED, since energy is lost in the resistor. More complicated circuits may be used to improve energy efficiency).
The LED used will have a voltage drop, specified at the intended operating current. Ohm's law and Kirchhoff's circuit laws are used to calculate the resistor that is used to attain the correct current. The resistor value is computed by subtracting the LED voltage drop from the supply voltage, and then dividing by the desired LED operating current. If the supply voltage is equal to the LED's voltage drop, no resistor is needed.
This basic circuit is used in a wide range of applications, including many consumer appliances. recommend directory: LED Strip RGB Amplifier.
Polarity
Unlike incandescent light bulbs, which illuminate regardless of the electrical polarity, LEDs will only light with correct electrical polarity. When the voltage across the p-n junction is in the correct direction, a significant current flows and the device is said to be forward-biased. If the voltage is of the wrong polarity, the device is said to be reverse biased, very little current flows, and no light is emitted. LEDs can be operated on an alternating current voltage, but they will only light with positive voltage, causing the LED to turn on and off at the frequency of the AC supply.
Most LEDs have low reverse breakdown voltage ratings, so they will also be damaged by an applied reverse voltage above this threshold. The cause of damage is overcurrent resulting from the diode breakdown, not the voltage itself. LEDs driven directly from an AC supply of more than the reverse breakdown voltage may be protected by placing a diode (or another LED) in inverse parallel.
The manufacturer will normally advise how to determine the polarity of the LED in the product datasheet. However, these methods may also be used. recommend directory: 8 Keys RGB RF Controller.
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would running an led with the appropriate resistor value on a 120dc current make the resistor too hot and melt?
i want to run 1 led on an 120vdc current, so if i put the right resistor on it would it be too much for lets say a 5k resistor and melt it?
Well, if you're using a 5K resistor it would blow up the LED more than likely, creating an open from ground thus disabling the resistor, if it didn't melt the resistor's leads first. Now, as you want to run the LED through a resistor(as 90% of the time lol), you would have to have the appropriate wattage rating for it. You will have to find a 3W resistor for this circuit if you were using the 5K, which draws 0.024A and 2.880W at 120V. Are you sure it's a DC source and not 120V AC as a wall outlet? Have fun finding an LED for 120V though. I'm half asleep when I'm posting this, so it might be hard to follow me and my calculations might be off, so please excuse that. Simple answer is: yes, but you have to have the right components and you'll need bigger than a 5K resistor.
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