A system for generating a tunable DC slope includes: a first stage, supplied with an external voltage, for receiving a process, voltage and temperature (PVT) insensitive reference voltage and generating a voltage independent current; a second stage, coupled to the first stage and supplied with the external voltage, for generating a voltage dependent current and summing the voltage dependent current and the voltage independent current to generate a sloped voltage; and a third stage, coupled to the second stage and supplied with the external voltage, for amplifying the sloped voltage, and tapping the resultant sloped voltage at a desired point for generating the output DC slope.