Synaptics Japan Gk

Synaptics Display Devices Gk

Toshiyuki Takani

Toshikazu Tachibana

Tatsuya Ishii

Takesada Akiba

Akihito Akai

Shinobu Notomi

For each display line cycle, inputs to a pair of differential input terminals of a driving circuit are alternately switched in a cycle shorter than the display line cycle between a gradation voltage and a reference voltage. According to this, a chopping operation of switching polarities of offset appearing at the output of the driving circuit within one display line is performed for a plurality of times, and accordingly, a pixel of each display line maintains brightness information in which the chopping operation is already performed. As a result, although a frame cycle is lengthened, it is difficult to visually recognize a brightness difference caused by the offset.

Driver IC for display panel

The touch panel controller is connected with a touch panel having a plurality of drive electrodes, a plurality of detection electrodes, and a plurality of capacitance components formed at intersections of the drive and detection electrodes. A two-edge detection mode is adopted for the touch panel controller, in which signals arising on each detection electrode in synchronization with rising and falling edges of a drive pulse output to the drive electrodes, and alternately changing in polarity are accumulated in the integration circuit in terms of absolute value components. The integration circuit switches the connection of the integration capacitance between an input and an output before the drive pulse edge changing. The touch panel controller contributes to the shortening of the time for touch detection by the touch panel and the increase of the accuracy of touch detection.

Semiconductor device and electronic device

Growing community of inventors

Tokyo, Japan

Toshiyuki Takani