Patent ID: 8314779
Filing Date: 2012-11-20
Classification: G06F

Abstract:
1. A controller for detection of touches by a single finger or multiple fingers on a touch panel, the touch panel including a first group of electrodes arranged in a first direction and a second group of electrodes arranged in a second direction, thereby forming a plurality of crossover points, the controller comprising: a plurality of signal drivers coupled to the first group of electrodes and configured to excite the first group of electrodes sequentially using a spread spectrum driving signal provided by an analog waveform generator using no code division multiplexing; a plurality of signal sensors coupled to the second group of electrodes and configured to detect peaks and troughs of capacitive coupled signals at the second group of electrodes, the detecting being performed simultaneously for the crossover points along a current one of the first group of electrodes that is being excited; and a signal processing device comprising an analog to digital converter (ADC) to convert analog signals from the signal sensors into digital data and a digital signal processing (DSP) unit configured to compensate the digital data, and to detect the touches, calculate touch positions, and generate touch images based on the compensated digital data, wherein the DSP unit comprises: