An electronic device used to measure a physical quaNTity such as temperature, pressure or loudness and convert it iNTo an electronic signal of some kind (e.g a voltage). Sensors are normally componeNTs of some larger electronic system such as a computer coNTrol and/or measuremeNT system. Analog sensors most often produce a voltage proportional to the measured quaNTity. The signal must be converted to digital form with a ADC before the CPU can process it. Digital sensors most often use serial communication such as EIA-232 to return information directly to the coNTroller or computer through a serial port. (1997-04-15)