Always on low power capacitive matrix autonomous scan

Disclosed are sensing systems and methods that eliminate CPU intervention or interrupts when performing sensor scans of a touch interface, supports low power sensing operation without requiring periodic wake up of the CPU, and is scalable to multi-channel or multi-chip sensor configuration to suppor...

Full description

Saved in:
Bibliographic Details
Main Authors Bharathan, Vibheesh, Kinane, Andrew
Format Patent
LanguageEnglish
Published 17.08.2021
Subjects
CALCULATING
COMPUTING
COUNTING
ELECTRIC DIGITAL DATA PROCESSING
PHYSICS
Online AccessGet full text

Cover

More Information
Summary:Disclosed are sensing systems and methods that eliminate CPU intervention or interrupts when performing sensor scans of a touch interface, supports low power sensing operation without requiring periodic wake up of the CPU, and is scalable to multi-channel or multi-chip sensor configuration to support large touch screens or a high number of sensors. A sensor scanning module may operate in a chained-scan using direct memory access (CS-DMA) mode or an autonomous scan-multiple scan (AS-MS) mode to perform scanning of all sensors within a frame without requiring CPU intervention or generating CPU interrupts after every scan in the frame. The sensor scanning module may operate autonomously in a low-power always-on scan (LP-AOS) mode for multiple frames without CPU interaction until a touch event is detected. The CPU may operate in a low power sleep mode during the scan while providing consistent refresh rate and low touch-to-system wake up latency.
Bibliography:Application Number: US202016824972