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# Two Color 3mm

![](/files/-MS2NQXZfHNhEHPxrGhs)

The 3mm bi-color LED has a common cathode (- pin), connected with the ‘-’ pin on the PCB. The centre pin activates the red light and the ‘S’ pin the green light. No series resistor is included in the circuit. A suitable value for low voltage operation would be 220 ohms.