Discussing the need to amplify sensor signals. Engine Control Units monitor a variety of systems, such as fuel level, temperature, and ambient conditions, by processing sensor signals using an MCU. An MCU receives sensor signals and then determines the process, but if the sensor is connected directly to the MCU, the sensor signal may be too small for the MCU to recognize. However, by inserting an OpAmp between the sensor and MCU, the designer can amplify the signal to support proper MCU operation. Sensor signal amplification is one of the main uses of OpAmps.