# How do you calculate a resistor for an LED?

## How do you calculate a resistor for an LED?

We’ll use the following formula to determine the resistor value: Resistor = (Battery Voltage – LED voltage) / desired LED current. For a typical white LED that requires 10mA, powered by 12V the values are: (12-3.4)/. 010=860 ohms. To use several LEDs in parallel, sum the current values.

## How is LED voltage calculated?

Calculating LED Power To calculate an LED’s power use, simply multiply the LED’s voltage (in volts) by the LED’s current (in amperes). The result, measured in watts, is the amount of power your LEDs use. For example, if your LED has a voltage of 3.6 and a current of 20 milliamperes, it will use 72 milliwatts of power.

**What is the forward current of an LED?**

Most common LED’s require a forward operating voltage of between approximately 1.2 to 3.6 volts with a forward current rating of about 10 to 30 mA, with 12 to 20 mA being the most common range.

### Why do you need 330 ohm resistor for the 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.

### How do you calculate current in an LED circuit?

R = (VS – VL) / I For standard 5mm diameter LEDs the maximum current is usually 20mA, so 10mA or 15mA are suitable values for many circuits. The current must be in amps (A) for the calculation, to convert from mA to A divide the current in mA by 1000.

**How many volts can a LED take?**

The maximum voltage applied it a single white LED is about 3.0 volts. Several LEDs in series can match a higher voltage supply, or a resistor (or other current limiting circuit) can be used to limit the current.

## How to calculate the value of resistor for led?

LED Resistor Calculator. To calculate the resistor needed for a simple LED circuit, simply take the voltage drop away from the source voltage then apply Ohm’s Law. In other words… where: V S is the source voltage, measured in volts (V), V LED is the voltage drop across the LED, measured in volts (V), I LED is the current through the LED

## How do you calculate a resistor?

B = 0.1%

**How to choose a resistor for a led?**

Choosing a resistor. So, how do you choose a resistor? First of all, you need to choose the resistance value. To do that you use Ohm’s law. One common example is to find the resistor value you need for an LED. Next, you need to consider the power that the resistor needs to dissipate. Power dissipation in a resistor can be calculated with the

### What kind of resistor do I need for led?

What kind of resistor do I need for LED turn signals? You will need 50W 6 OHM load resistors and tap the load resistor to the stock harness in parallel. Load resistors also have no negative or positive, making it easier for you because you wouldn’t have to worry about which wires goes to which side.