Abstract: A signal conditioner for converting non-standardized analog signals from a variety of sensors of temperature, pressure, and flow rate, into standardized signals which are accurately readable by a computer; wherein an analog to digital converter converts the non-standardized analog signal into a digital signal, arithmetic circuit effects a predetermined arithmetic operation on the digital signal, pulse outputting circuit takes the arithmetic results and generates a pulse signal having duty ratio corresponding thereto, and filter circuit smooths the pulse signal and generates the standardized signal which represents the non-standardized analog signal from the different sensors.