METHOD AND APPARATUS FOR ENHANCING TOUCH SENSING IN A DISPLAY PANEL

摘要

Driving a touch-sensing-enabled active matrix LCD display panel for enhancing touch sensing by reducing parasitic capacitances is considered. In one embodiment, a plurality of driving voltages is generated. The driving voltages include a common voltage, and a first and a second gate-drive reference voltages for configuring a thin film transistor (TFT) in the panel to switch on and off, respectively. When the panel is operated in a sensing mode, the common voltage that is generated includes a pulse-train waveform. Furthermore, each of the first and the second gate-drive reference voltages is substantially time-synchronized to and includes the pulse-train waveform of the common voltage during the sensing mode. In one option, the driving voltages further include a sensing-mode source-drive voltage acting as a source-drive signal for the TFT during the sensing mode. The sensing-mode source-drive voltage is substantially time-synchronized to and includes the pulse-train waveform of the common voltage.

主权项

1. An apparatus for driving a touch-sensing-enabled active matrix LCD display panel, the panel being configurable to be operated in a display mode or in a sensing mode, the apparatus comprising:
one or more voltage generators for generating a plurality of driving voltages, the plurality of driving voltages including a common voltage for powering a backplane of the panel, a first gate-drive reference voltage receivable by a gate of a thin film transistor (TFT) in each LCD cell of the panel for configuring the TFT to switch on during the display mode, and a second gate-drive reference voltage receivable by the gate of the TFT for configuring the TFT to switch off during the display mode; wherein the one or more voltage generators are configured such that: when the panel is operated in the sensing mode, the common voltage that is generated includes a pulse-train waveform; and each of the first and the second gate-drive reference voltages is substantially time-synchronized to and includes the pulse-train waveform of the common voltage during the sensing mode.