Finally, the signal output section offers two digital outputs (pins 2 and 3) and one analog output (pin 5) which measures the voltage across the phototransistor load resistor. The analog output allows the design engineer to set any reference point to recognize an optical change for the device being monitored. The analog output can also be used with reflective sensors to monitor small changes in distance. The board also provides visual outputs with a Blue LED connected to digital output B and a Green LED connected to digital output A.