Resume

• 1970

  Ph D

  Electrical Engineering

  IEEE

• ASIC

  Digital Signal Processors

  Power Management

  Semiconductors

  Circuit Design

  Signal Processing

  Wireless

  Biomedical Engineering

  VLSI

  Analog Circuit Design

  Verilog

  Hardware Architecture

  CMOS

  Analog

  Mixed Signal

  Cadence Virtuoso

  ModelSim

  IC

  Integrated Circuit Design

  Simulations

  An Automatic Resonance Tracking Scheme With Maximum Power Transfer for Piezoelectric Transducers

  Keith Malang

  Daniel A. Friedrichs

  This paper presents a novel cost-effective automatic resonance tracking scheme with maximum power transfer (MPT) for piezoelectric transducers (PT). The conventional approaches compensate the PT with complex power factor correction schemes or drive it in resonance using intricate loops with limited operating range. The proposed tracking scheme is based on a band-pass filter (BPF) oscillator

  exploiting the PT’s intrinsic resonance point through a sensing bridge. It guarantees automatic resonance tracking and maximum electrical power converted into mechanical motion regardless of process variations and environmental interferences. Thus

  the proposed BPF oscillator-based scheme was designed for an ultrasonic vessel sealing and dissecting (UVSD) system

  where accurate PT displacement regulation over a wide range of loads is required. An amplitude control for a switching power stage was developed to regulate the output mechanical motion and provide different power levels for the specific surgical functions such as sealing and dissecting. A proportional-integral (PI) compensator was developed to ensure stable operation under various loading conditions. The sealing and dissecting functions were verified experimentally in chicken tissue and glycerin.

  An Automatic Resonance Tracking Scheme With Maximum Power Transfer for Piezoelectric Transducers

  Edgar

  Sanchez-Sinencio

  Vidatronic Inc

  Texas A&M University

  College Station Texas

  Vidatronic Inc

  Texas A&M University

  Dept of ECE

  Texas A&M University

  Director of the Analog and Mixed-Signal Center

  TI J. Kilby Chair Professor and University Distinguished Professor

  This patent is on a sleep apnea detection algorithm and its circuit level implementation in IC design.

  SLEEP APNEA DETECTOR