Package level integration of a monolithic buck converter power IC and bondwire magnetics

In this paper, we report a concept of integrating a monolithic buck converter power IC with in-package bondwire inductors. The power IC was designed and fabricated with a standard 0.5µm CMOS process. Multi-turn bondwires with and without ferrite epoxy glob cores are used as the filter inductor in the buck converter. A 2.5V/120mA prototype system in package (SiP) buck converter is built to operate at frequencies up to 5MHz. The power level of the prototype buck converter is scalable by increasing the size of the active power switches.