Clustered scan method of a capacitive touch device

Abstract

A clustered scan method of a capacitive touch device has steps of simultaneously providing driving signals in one driving cycle to multiple driving lines including the (i−j)th drive line to the (i+k)th drive line, and simultaneously providing driving signals in a next driving cycle to the drive lines including some of the drive lines driven in the previous driving cycle with a sum of the driving signal in each driving cycle greater than zero. When the stimulated drive lines include a bordering drive line, the driving lines are determined according to a relationship among i, j and k. Accordingly, the signal to noise ratio of the touch device can be increased and the adverse effect for common ground occurring between a measuring system and a human body can be reduced so that the multi-finger positioning issue can be resolved.

Description

technical field [0001] The invention relates to a scanning method of a capacitive touch device, in particular to a cluster scanning method of a capacitive touch device. Background technique [0002] At present, there are two common scanning methods for capacitive touch devices: self-capacitance scanning method and mutual capacitance scanning method; among them, the mutual capacitance scanning method proposes a variety of different mutual capacitance scanning methods according to the different needs of capacitive touch devices. The cluster scanning method is one of them. The following outlines a variety of different cluster scanning methods for illustration. [0003] For example, U.S. Patent No. 7,812,827 discloses a "SIMULTANEOUS SENSING ARRANGEMENT" (simultaneous sensing configuration) technology, which is also used on a capacitive touch device that consists of multiple driving lines and sensing lines interlaced to form multiple sensing points. This technology enables enha...

AI Technical Summary

Problems solved by technology

When using a single positive voltage waveform or a negative positive voltage waveform to drive a driver, in addition to the mutual capacitance (Mutual Capacitor) between the driving line and the intersecting sensing line, when an object such as a finger approaches, the driving line and the finger There will be a parasitic self-capacitance between the sensing line and the finger. If the finger and the touch system do not share the same ground, the sensor (Sensor) will be affected by these parasitic self-capacitance influence, and interact with the interaction capacitance on the sensor during operation, which makes the measured capacitance value of the interaction capacitance distorted, especially in the case of poor common ground between the measurement system and the human body, it will be more serious

Images