MTL Annual Report

Figure 1: Die photo of the low-voltage cascoded MOSFETs along with its on-chip oscillator and gate drive.

The size of power conversion electronics is a dominant obstacle to achieving further miniaturization and integration of many modern mobile and communication systems. To realize miniaturization, integration, and increased bandwidth, it is necessary to develop new types of power converter circuits capable of operating at dramatically increased switching frequencies and higher tracking bandwidth while maintaining high efficiency.

This research explores development of integrated low-voltage power devices and integrated gate drives and their use in low-voltage power converters operating at very high frequencies.  Optimization of CMOS device layouts for use in VHF switching power converters is considered, and cascode device stacks are developed for an extended operating voltage range.  Design of integrated gate drives for the switches is also explored.

Figure 2: A resonant boost topology via which the merits of VHF power conversion with optimized devices can be shown.

Utilizing these integrated low-voltage devices and on-chip gate drives, we are also investigating topologies for VHF operation at low voltages (e.g., including synchronous rectification).  These low-voltage power converters are expected to achieve high efficiencies (to beyond 90%) at high switching frequencies (to beyond 150 MHz) and to enable substantial miniaturization and improved bandwidth of dc-dc converters in this space.