In this article we investigate the IC X9315 which is actually a solid state digital potentiometer and could be used exactly like a mechanical potentiometer, but through logical supply inputs. The IC X9315 from Intersil, is a digitally controlled solid state potentiometer, which internally possesses an array of resistors, wiper switches, a controlling system, and a non-volatile memory section. The IC utilizes a 3 wire interface for controlling the various positions of the wiper, and the potentiometer function is implemented through the array of resistors which are 31 numbers of resistive network, associated with the wiper switching network. The entire array along with the end points of this resistive network are all integrated with the wiper network such that the wiper is able to access any point of the resistor array for executing the corresponding values of the potentiometer output through the 3 wire interface. The CS, U/D and the INC pinouts of the IC actuall...