A DC-DC converter transitions between continuous conduction mode (CCM) and discontinuous conduction mode (DCM) without causing any overshoot or undershoot deviation output voltage. The DC-DC converter operates in a PWM mode in CCM. During DCM, it skips PWM pulses when a sustained negative current is detected in an output inductor. The current sensing is achieved by sampling and integrating a voltage, the sign of which is inverse to current direction. The sample and hold and integrator circuits are small, simple, and scale to high frequencies. The pulse skipping circuit automatically adjusts the duty cycle of power pulses to force a zero inductor current at the end of each pulse.