I really cannot understand what will be the difference if the charge/discharge will be linear or exponential relative to the pot circuit. As long as the pot is at a position the capacitor will charge and stay at that charge. A new pot position will give little or more change at the output but then again it will stabilize at the new level.
A current source will charge the capacitor linearly (Q=C*V, Q=I*t, t=C*V/I).
But as is your example, I don't know how it can be accomplished or what the result would be. The Current source will charge the capacitor and then will stop function because there will be no current to flow untill you will change the pot to a higher level. For a lower level a second curent source would be needed to discharge.
Ioannis
Bookmarks