CHIP PORTFOLIO
Explore Hao-Yen Tang's chip work across ultrasonic fingerprint imaging, touch and force sensing, medical ultrasound, and energy harvesting. Each program shows the device, his role, and the papers or patents behind it.
IMAGING ASIC
SURFACE + SUBSURFACE
Schematic illustration
| Real finger | PDMS replica | |
|---|---|---|
| Surface | Real finger · surface | PDMS replica · surface |
| Inner layer | Real finger · inner layer | PDMS replica · inner layer |
Chip lead and inventor · UC Berkeley · 2012-2016
The thesis chip. A PMUT array bonded to CMOS that images a fingerprint in three dimensions, including the ridge structure below the skin surface. It became the prototype for a commercial fingerprint sensor product line.
Chip lead and inventor · array and circuit co-design, high-voltage pulser, beamforming
Piezoelectric micromachined ultrasonic transducers built monolithically on CMOS: the sensor, its analog front end, and an MCU on one die. The imaging chain reads a fingerprint through glass and metal by transmit beamforming and pulse-echo timing.
Chip lead, multiple generations · mixed-signal front end, high-voltage pulser, system bring-up
An ultrasound touch and force controller that turns an ordinary surface into a button. Sensor, analog front end, MCU, and the sensor-fusion algorithm all live on one chip, so a button can be placed behind metal with no hole and no moving part.
Chip lead · architecture, mixed-signal front end, high-voltage pulser, on-chip sensing algorithm
A multi-modal human-machine-interface SoC: capacitive touch, ultrasound touch and slider, and piezoelectric force sensing, fused on-chip. One part replaces the controller, the discrete force front ends, and the glue between them.
Chip lead · architecture, mixed-signal front end, high-voltage drive, sensor fusion
A controller that keeps a camera lens clear by driving it ultrasonically. One chip carries the power conversion from the vehicle battery, the piezo driver, an on-chip Hall-effect current sensor that tracks the transducer's resonance, and the digital control.
Chip lead · architecture, piezo driver, on-chip current sensing
A time-of-flight rangefinder on a chip, small enough and low-power enough to sit in a consumer device. Precision frequency demodulation and low-jitter time measurement are what make a centimetre-scale echo readable at microwatt power.
Analog designer, prototype and first production generation · high-voltage pulser, PLL and frequency demodulation, mixer and filter design
A handheld, battery-powered ultrasound imager demonstrated at ISSCC. The interesting part is the drive side: getting enough voltage into a discrete piezo element from a battery, efficiently enough that the whole instrument runs at milliwatts.
Chip lead · high-voltage drive, integrated charge pump
A millimetre-scale implant that records neural activity and is powered and read out by ultrasound through tissue, with no battery and no wire. I built the ASIC the prototype used; the work went on to seed iota Biosciences.
ASIC provider · ASIC design, ultrasound wireless power transfer
A DC-DC converter that starts up from 50 mV with no battery and no external kick, turning the few tens of millivolts a thermoelectric generator produces into a usable supply rail. My first silicon, and still my second most-cited paper.
Chip lead · converter architecture, startup circuit
A large-area ultrasonic fingerprint sensor built on a thin-film transistor backplane with a piezoelectric polymer film, driven by a companion ASIC.
Analog designer · high-voltage drive, transmit beamforming
