— A quadratic slope compensation scheme for a current-mode DC-DC converter to obtain stable frequency characteristics without depending on the input and output voltages is proposed. A 5 MHz and 500 mA buck DC-DC converter with input voltages ranging from 3.3 V to 2.5 V and with output voltages ranging from 2.5 V to 0.5 V was fabricated by using a 0.35 μm CMOS process to verify the effectiveness of the scheme. Little variation of frequency characteristics at frequencies above 200 KHz for the various input and output voltages was observed.