From Murmann Mixed-Signal Group
BSEE, Tsinghua University, 1996
MSEE, University of Toledo, 1998
Ph.D, Stanford University, 2014
Research: Densely Integrated Interface Circuits for Structural Health Monitoring
A promising approach in aerospace Structural Health Monitoring (SHM) is embedding a large-scale piezoelectric transducer array into the aircrafts’ structure to detect defects during service. Building the interface electronics of the large-scale array in IC form is essential to the embeddability of the whole system. The challenge is driving the piezoelectric transducer with a precise waveform at high voltages and ultrasonic frequencies. We propose a solution using pulse width modulation (PWM), in which the tone-burst signal is rendered by a series of precisely timed pulses. A calibration technique is introduced to achieve sub-nanosecond timing accuracy and -40.5 dB signal distortion.
We fabricated a four-channel, ±36 V, 780 kHz piezo driver chip in 0.25 micron BCD (Bipolar-CMOS-DMOS) technology. The IC was successfully evaluated within an application test bed.
We are working on the next generation design, which is an eight-channel SHM IC with both the driving and receiving circuits in each channel.
Email: alexguo AT stanford DOT edu