Scan method for a touch panel and touch device

摘要

The present invention relates to a scan method for a touch panel and a touch device. It operates two different Analog-to-Digital Converter calibrations to have different baselines and thresholds corresponding respectively to a cursory scan mode and a fine scan mode. In cursory scan mode, multiple traces are driven simultaneously and the signals from the traces are received simultaneously to enlarge the sensing value so that a touch object with a lower sensing signal is also detected. Further, the cursory scan mode with less electricity cost is used to first determine whether touch objects exists. When the touch objects do exist, the fine scan mode with more electricity cost is then operated. Therefore, the present invention can further reduce the electricity waste.

主权项

1. A scan method for a touch panel comprising steps of:
executing a first Analog-to-Digital Converter calibration (ADC calibration) for a cursory scan mode to get a first baseline and setting a first threshold based on the first baseline; executing a second ADC calibration for a fine scan mode to get a second baseline, and setting a second threshold based on the second baseline; entering in the cursory mode or the fine scan mode; in the cursory mode, driving i traces and receiving multiple first sensing signals of j traces simultaneously and comparing the first sensing signals with the first threshold to determine whether at least one touch object exists; if the at least one touch object exists, then entering the fine scan mode, wherein “i” and “j” are positive integers that are bigger than one; in the fine scan mode, driving multiple first groups of the traces in sequence, wherein each first group of the traces includes k traces; receiving multiple second sensing signals from multiple second groups of the traces, wherein each second group of the traces includes h traces; and determining a coordinate of each one of the at least one touch object by the second sensing signals and the second threshold, “k” is a positive integer that is smaller than “i” but is bigger than one, and “h” is a positive integer that is bigger than or equal to one.