3D IC design of a fully integrated four-phase buck converter

This paper presents 3D IC design of a fully integrated four-phase buck converter. The control circuit was implemented in the TSMC 0.18μm CMOS Mixed Signal RF General Purpose MiM Al 1P6M 1.8 & 3.3V process while the passive components were implemented in the tMt Glass Substrate Integrated Passive Device (IPD) Process, and then these two dies are stacked. Thus, a high output loading current can be obtained with a small chip area. The supply voltage is converted from 1.8V down to 1V with output ripple less than 70mV. The switching frequency is 50MHz and the maximum load current is 500mA, with 5mV/A load regulation and 2mV/V line regulation.