PROJECT TITLE :

A 1 mm Pitch Channel 322 Hz Frame-Rate Multitouch Distribution Sensor With Two-Step Dual-Mode Capacitance Scan

ABSTRACT:

A one mm pitch eighty X eighty channel 32two Hz framerate capacitive multitouch distribution sensor has been developed. High-resolution multiple bit points are detected as well as bit-strength distribution around them. A two-step twin-mode capacitance scan theme is proposed, where self- and mutual-capacitance measurements are hierarchically performed in two steps to increase the frame scan rate that's otherwise reduced thanks to high resolution. one hundred sixty row-and-column dedicated parallel ADCs further increase the scan rate. A time-domain counter-based slope ADC suppresses power and space penalty for the parallel ADC approach. A signal attenuation because of the sensor capacitance reduction within the high resolution is compensated by thorough noise-reduction techniques within the sensor analog frontend (AFE). A prototype in zero.35 μm CMOS demonstrates forty one dB signal-to-noise ratio (SNR) with >5× tighter sensor-channel pitch, >ten× faster touch-point scan, >10× and >four× higher energy and area potency to the state-of-the-art touch distribution sensors.