National Chiao-Tung University

Department of Electronics Engineering & Institute of Electronics





Near-/Sub-threshold PVT Sensors for Micro-Watt DVFS System Design






Student : Shi-Wen Chen

Advisor : Dr. Wei Hwang



Abstract

The goal of this research is to design and implement PVT sensors for micro-watt DVFS system design. It includes the design of self-calibration all-digital PVT sensors, MTCMOS switched capacitor (SC) DC-DC converter, temperature compensation for low-voltage digital assist PLL, and dynamic voltage and frequency scaling system. The major contributions are as below:

  1. A near-/sub-threshold all-digital process, voltage, and temperature sensor is proposed and integrated to the DVFS control for micro-watt system applications. The sensor is proposed for high accuracy, ultra-low voltage, low power, and self-calibration portable applications.
  2. A self-calibration near-/sub-threshold all-digital temperature sensor with adaptive pulse width generator is proposed. The sensor is proposed for high accuracy, ultra-low voltage, low power, and self-calibration portable applications.
  3. A PVT-aware DVFS for micro-watt system is proposed. The system through the switched capacitor (SC) DC-DC converter can provide a very stable DC power supply. It generates different voltage levels which are suitable for SoC integrated regulator applications.
  4. A novel connect scheme for improving power efficiency and reducing voltage variation of switched capacitor (SC) DC-DC converter which generates ultra low voltage is proposed.
  5. Proposed a temperature compensation for low voltage digital assist PLL can modulate output frequency via divider. Use the temperature sensor to compensate the frequency can not lock in the worth case.