MC3x063A Monolithic Inverting Regulators onsemi MC3x063A Monolithic Inverting Regulators are monolithic control circuits containing the primary functions required for DC-DC converters. Buck, Boost, and Inverting topologies are available. These devices consist of an internal temperature-compensated reference, comparator, and controlled duty cycle oscillator with an active current limit circuit, driver, and high current output switch. This series was designed to be incorporated in Step-Down/-Up and Voltage-Inverting applications with a minimum number of external components.