The ultimate memory game
Placed onLEDs
An LED is a low consumer. This means that it will require very little current and voltage, but unfortunately this also means that if it receives too much current/voltage, it will burn out. To prevent an LED from burning out, we connect a resistor in series with the LED. We can calculate the resistance value of the resistor based on the LED characteristics. You can find this in the datasheet of the LED. Suppose we want to set the LED to 10mA, so we have to put voltage about 3.2v across the LED. In a series circuit, the sum of the partial voltages is equal to the source voltage, and the current through each component is the same. The known partial voltage is 3.2v, so the voltage across the resistor must be 1.8v. The current through the resistor is 10mA, so now it's just applying Ohm's law: U = IR => R = U/I. 1.8/10*10^-3=180Ohm. So we need to put a 180 ohm resistor in series with the resistor.
