linear capacitor charge circuit

[waltsar]

Hi, this is my first post. I am trying to find a simple way to build a circuit that will charge a capacitor linearly ( as opposed to exponentially).

I'm using a 12VDC unfiltered power supply (this is necessary for other reasons). This circuit will provide the reference voltage for an LM339 comparitor.

Thank you,
Walt

[pebe]

You could configure a transistor as a constant current generator. Do you want a circuit?