Created on: 30 November 2017
Pinout for the Geekcreit common cathode Red & Green LED module, and the two color common cathode LED module from the Geekcreit 37 in 1 sensor module board set kit for Arduino.
These two modules are identical except that one module has a 5mm LED and the other has a 3mm LED. Both modules contain a 3-pin 2 colour LED. The LED has a common cathode pin and can display a red or green colour depending on which anode pin power is connected to.
Below are images with pinouts for the two modules. The modules must be used with current limiting resistors. Resistor R1 on the module is a 0 Ohm resistor that does not provide any current limiting.
Below is the 5mm two colour LED module.
The image below shows the 3mm LED module, which may be called the mini LED module in some kits.
As can be seen in the above images, with the LED facing up, the left most pin is the common cathode which connects to GND or negative of the power supply.
The middle pin connects to the red LED anode which connects to the positive of the power supply. It must be connected to the power supply through a current limiting resistor.
The right pin connects to the green LED anode which connects to the positive of the power supply. It must be connected to the power supply through a current limiting resistor.
Below is an electrically equivalent circuit diagram of the common cathode LED module. Although the circuit does not show the zero Ohm resistor, the circuit represents the electrical connections and pins of the module.
The common cathode red and green LED module Arduino tutorial shows basic use and testing of this module with Arduino.