# Series LEDs

LEDs that are connected in series have only 1 current path through them. Therefore, they are guaranteed to have the same amount of current flowing through them.

The forward voltage drops of LEDs add up when connected in series.

• If you just have a 1,000 ohm resistor, powered with 5V, then it will have 5V across it. 5V/1,000Ω = 0.005A (same as 5mA) of current will flow through it.
• One 2V forward drop LED in series with a 1,000 ohm resistor will drop 2V from the resistor, so that only 3V is across the current setting resistor when powered with 5V. Setting the current through the circuit to 3V/1,000Ω = 0.003A (same as 3mA).
• Two 2V forward drop LED in series with a 1,000 ohm resistor will drop a total of 4V from the resistor, so that only 1V is across the current setting resistor when powered with 5V. Setting the current through the circuit to 1V/1,000Ω = 0.001A (same as 1mA).

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