What is the function of resistance in the circuit of LED?

What is the function of resistance in the circuit of LED?

Generally, it is used to limit current and protect led, because the rated current of small diode is only 10mA, too much current will burn the diode, so resistance current limiting protection is used

In an electronic circuit, what is the function of a resistor in series before or after the LED lamp? How to choose the size of the resistor?

The main reason is the power supply voltage; higher than the LED voltage, the resistance is to reduce the voltage. The resistance value selection should first calculate the LED lamp resistance, calculate the resistance value according to the partial voltage ratio, and calculate the resistance power with I ^ 2R according to the LED current

What role can series resistance play in circuit

Series voltage division, parallel shunt, more voltage, series off extra voltage, current, parallel off current, control the desired rated current

How to know the size of resistance and capacitance

Brown 1, red 2, Orange 3, yellow 4, green 5, Blue 6, purple 7, gray 8, white 9, black 0, the maximum value of the first circle and the second circle of gold and silver have no change, the value of the third circle is a multiple of 10, 100, 1000... 1000000000 respectively, the black is 1, and the gold and silver are only meaningful in the third and fourth circles, the error is 0.10.01 respectively, the error is 5% and 10% respectively, It just means that the error is 20%. Is that what you want?