The AD1868 has two ground pins, designated as AGND (Pin 12) and DGND (Pin 7). The analog ground, AGND, serves as the “high quality” reference ground for analog signals and as a return path for the supply current from the analog portion of the device. The system analog common should be located as close as possible to Pin 12 to minimize any voltage drop which may develop between these two points, although the internal circuit is designed to minimize signal dependence of the analog return current.