PMIC (Power Management Integrated Circuit) DC to DC switching controllers are voltage regulation ICs used in high efficiency circuits configured to generate output supply voltages above (boost or step-up) or below (buck or step-down) the input supply. Other topologies may include; buck-boost, flyback, forward, cuk, SEPIC, full bridge, half bridge, and push-pull. They differ from linear regulators that require minimum voltages and "burn off" excess voltage.