Projects and Students

 

Ongoing Research Projects:

 

1. Wireless Power Transfer (WPT) Systems. In this project, we develop efficient WPT system to transmit power wirelessly to support applications with different power levels, from Watt-level for smart-phone/laptop charger, to miliWatt-level for biomedical implants. Students will be designing the power transmitter, wireless power link (coils for inductive coupling), and power receiver. This project is focusing on improving the performance of WPT systems, including the efficiency, transmission distance, power capacity, dynamic performance during transient events, as well as reducing the form-factor and cost.

Students involved: Junyao Tang (PhD Student); Shuo Xie (MS Student); Hoang Dang (Undergraduate Student).

 

2. High-Frequency Fully-Integrated Voltage Regulators (FIVRs). Voltage regulators are fundamental in any electronics to bridge the gap between: the unregulated single voltage from the sources (e.g., the Li-ion battery, with which the actual output voltage varies from 2.8 to 4.2 V depending on the condition of the battery), and the multiple well-regulated voltages needed in different building blocks in a system (e.g., CPU, Memory, I/Os, data converters, sensors, they need different voltages to operate, and the voltage has to be accurate). This project is to design FIVRs with all the components, including the passive inductors and capacitors, integrated at the chip or package level. They will be switching at a relatively high frequency (e.g. 100 MHz). This project is focusing on improving the performance of FIVRs, including the power efficiency, capacity, load-/reference-tracking speed, reliability, voltage and load range, as well as reducing the form-factor and cost (hence higher power density).

Students involved: Lei Zhao (PhD Student); Julián Canabal-Rodríguez and Samuel Rosette (APEX-E Undergraduate Students).

 

3. Single-Inductor Multiple Output (SIMO) Voltage Regulators. Multiple voltage supplies are common in almost any electronic device to support various blocks in the system or SoCs. High efficiency inductive switchers are widely used to provide these supplies, however, the power inductors are bulky and expensive. The beauty of SIMO converters is that it can increase the number of voltage supplies without introducing extra inductors, which significantly reduces the BOM (bill of materials), hence the cost, form-factor and system design complexity. This project is focusing on improving the cross-regulation and power capacity of SIMO converters, so that they behave as near-independent voltage regulators.

Student involved: Sangwon Lee (MS Student).

 

4. Galvanic Isolated Voltage Regulators (GIVRs). GIVRs are widely used to supply low-voltage sensing, processing and control circuits with galvanic isolation from hazardous environment, such as industrial automation that high-voltage domain or destructive voltage surge exist. This project is to develop small form-factor GIVRs that can be integrated inside an integrated circuit package with high efficiency and power density.

Student involved: Junyao Tang (PhD Student).

 

5. Gallium Nitride (GaN) Based Power Converter Designs. We believe that wide-bandgap semiconductors, such as GaN devices, will lead to a revolution in power electronics with much higher efficiency due to their superior material properties. So our group will be developing new circuit and system techniques to achieve high efficiency, high power density, robust, and fast power management circuit designs.

Student involved: Si Yuan Sim (Undergrad Student).

 

Chip Gallery

 

Future Research Projects: 

 

Energy harvesting for wireless sensors, High-ratio DC-DC converters for Data Centers, High-power kW-level WPT system for electric vehicles, and more.