The AD5293 asks for an external capacitor of 1uF, 7V on the EXT_CAP pin. But there is no mention of what this pin is really doing in the internal circuit. Do i need to be concerned about leakage or distortion in the capacitor i.e. from using an electrolytic or ceramic? Perhaps it is bypassing some digital circuitry and I need a tantalum? Will I see a noticible decrease in distortion with a polyester type? I am concerned with minimizing the distortion while still having a simple digitally controlled variable potentiomter in my design.