Described examples include DC-DC power conversion systems, apparatus and methods for linearizing a DC-DC circuit conversion gain, including a gain circuit providing an output signal according to a gain value and the difference between a first compensation signal and a threshold signal, and a switching circuit selectively operative when the first compensation signal exceeds the threshold signal to linearize the conversion gain by providing a second compensation signal for pulse width modulation of at least one DC-DC converter switch according to the threshold signal and the gain circuit output signal.