Abstract: An AD conversion apparatus includes an AD conversion unit; a reference voltage switching unit that is disposed between an output of a sensor and an analog input terminal of the AD conversion unit and is connectable to the output of the sensor and a plurality of reference voltage lines; and a control unit to control switching the reference voltage input to the AD conversion unit by connecting the reference voltage switching unit to one of the reference voltage lines and to the output of the sensor. An analog output value of the sensor is input to the analog input terminal of the AD conversion unit via the reference voltage switching unit and is converted into a digital value.

Abstract: An AD conversion apparatus includes an AD conversion unit; a reference voltage switching unit that is disposed between an output of a sensor and an analog input terminal of the AD conversion unit and is connectable to the output of the sensor and a plurality of reference voltage lines; and a control unit to control switching the reference voltage input to the AD conversion unit by connecting the reference voltage switching unit to one of the reference voltage lines and to the output of the sensor. An analog output value of the sensor is input to the analog input terminal of the AD conversion unit via the reference voltage switching unit and is converted into a digital value.

Abstract: The present invention relates to a semiconductor device and, more particularly, has for its object to provide a technique for improving the performance of a semiconductor device having a ground terminal and a plurality of signal terminals arranged around the ground terminal. To attain the object, the present invention features isolation between a ground terminal (5, 35) connected to a functional block (11) and a ground terminal (6, 36) connected to a functional block (12). Thus, a ground potential applied to one of the functional blocks through the corresponding ground terminal is prevented from varying depending on the magnitude of a current flowing through the other functional block. This improves the performance of each functional block to improve the performance of the semiconductor device.