Compare Serial I/O and Linear Analog Voltage Output in the GSS COZIR and SprintIR Carbon Dioxide Sensors.
By default, all COZIR and SprintIR carbon dioxide sensors use serial I/O (input/output). However, if you look closely, you can see the sensors also include a linear/analog voltage output pin. We always recommend ignoring the analog output and using the default serial I/O anyway. There are 3 reasons why.