# Question: Do you need a resistor for LED?

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An LED (Light Emitting Diode) emits light when an electric current passes through it. The simplest circuit to power an LED is a voltage source with a resistor and an LED in series. If the voltage source is equal to the voltage drop of the LED, no resistor is required.

## How do I know what resistor to use with LED?

Resistor = (Battery Voltage – LED voltage) / desired LED current. So assuming a 12-volt power source and a white LED with the desired current of 10 mA; The formula becomes Resistor = (12-3.4)/. 010 which is 860 ohms. Since this is not a standard value I would use an 820-ohm resistor.

## Why do we need a resistor in series to an LED?

The slightest difference in LED or supply voltage may cause the LED to light very dim, very bright, or even destroy. A series resistor will ensure that slight differences in voltage have only a minor effect on the LEDs current, provided that the voltage drop across the resistor is large enough.

## Do you need resistor for LED Arduino?

The short answer is, yes and no, it depends on your arduino and it depends on the color of your led. For instance, a 3.3V board does not require a resistor in series with a small green LED, because the forward voltage of the LED is pretty high, see this.

## Do 12V LEDs need resistors?

LEDs can be ran off multiple voltages, but a series resistor is required to limit the current in the circuit. Too much current in an LED will destroy the device. As with all diodes, LEDs will only allow current to flow in the direction from the anode to the cathode.

## What happens if no resistor?

If there really were no resistance in the circuit, the electrons would go around the circuit, and arrive back at the beginning of the circuit with as much energy as the potential difference (the voltage). That final energy is usually what is dissipated as heat or other types of energy by the circuit.

## What happens if you put too much voltage through an LED?

Simply put, too much voltage kills the LED. Therefore, if the voltage deviates more than 10%, the LED bulb is fused off. Subsequently, the electronic parts inside the LED bulb get damaged from the voltage spike.

## Why do you need a 330 ohm resistor for an LED?

Detail: 330 ohms may be used by some people as a get you going value that works well enough in many cases. The purpose of the resistor is to drop voltage that is not required to operate the LED, when the LED is operating at the desired current.

## Does a 12v LED need a resistor?

LEDs can be ran off multiple voltages, but a series resistor is required to limit the current in the circuit. Too much current in an LED will destroy the device. As with all diodes, LEDs will only allow current to flow in the direction from the anode to the cathode.

## Do resistors go on positive or negative side of LED?

Since this resistor is only being used to limit current through the circuit, it can actually be located on either side of the LED. Placing the resistor on the positive (anode) side of the resistor will have no differing effects from placing the resistor on the negative (cathode) side of the LED.

## What resistor do I need for Arduino LED?

In most of the getting started tutorials for Arduino (like this Blink example) it is recommended that we have place a 220 Ohm resistor.

## When should I use a resistor?

The main function of resistors in a circuit is to control the flow of current to other components. Take an LED (light) for example. If too much current flows through an LED it is destroyed. So a resistor is used to limit the current.

## How do I connect 220 volts to LED?

Lower wattage of resistor like 1/2 watt or lower will not do and may burn since they are meant for 6v DC circuits, not for 220v AC Mains .Assembly:Connect black anode of diode to negative of the led.connect the resistor to the positive of the LED.Connect the free ends of the diode and resistor to the male pins.

## Are all LEDs 12V?

Despite some of the most popular power supply voltage options being 12V or 24V DC, its important to remember that (most) individual LEDs are actually 3V DC devices.

## What happens if you connect a capacitor without a resistor?

Without a load, current will not flow through a circuit, and will thus not charge a capacitor in the circuit. Instead of using a resistor as a load in order to charge a capacitor, any other load can be implemented. If a resistor is not available, a light bulb of appropriate voltage may be used.

## What is the point of a resistor?

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses.

## Do LEDs get brighter with more voltage?

Supplying Power Adjusting the voltage lower or higher will change the brightness, but only because it also changes the current- higher voltage means the current will increase in an LED.

## What is the maximum voltage a LED can withstand?

LED V/I characteristicsCharacteristicsUnitMaximumForward voltage (@350mA, 85°C)V3.48

## Do 12v LEDs need resistors?

LEDs can be ran off multiple voltages, but a series resistor is required to limit the current in the circuit. Too much current in an LED will destroy the device. As with all diodes, LEDs will only allow current to flow in the direction from the anode to the cathode.

## How many LEDs can a 12V battery power?

A 12V battery wired to four 3V LEDs would distribute 3V to each of them. The same 12V battery wired to four 3V LEDs in parallel would deliver the full 12V to each of them. A single low voltage power supply can be shared by many LEDs.