Elan Microelectronics Corporation

Shih-Yuan Hsu

I-Shu Lee

Chun-Chung Huang

Te-Sheng Chiu

Yi-Hsin Tao

Chia-Hsing Lin

Wen-Jun Hsu

A transconductance amplifier mirror circuit is connected to an electrode for sensing the capacitance of the electrode with reference to ground, or the capacitance between the electrode and another electrode. A voltage level change is produced on the electrode connected to the transconductance amplifier mirror circuit to cause the transconductance amplifier mirror circuit to supply charges to or drain charges from a charge calculation circuit. The charge amount variation is converted to a signal for calculating the sensed capacitance.

Circuit and method for sensing a capacitance

Two sensing units are configured as an exciter and a sensor connected to two trace lines, respectively, for mutual capacitance sensing from the capacitance units including these two trace lines. The two sensing units connect the two trace lines together to balance them to a same voltage level first, and then disconnect them from each other. Thereafter, the exciter connects the first trace line to an excitation node to induce a charge change on the second trace line, and the sensor senses the charge change to detect the variation of the mutual capacitance between the two trace lines.

Sensing unit, sensing arrangement and sensing method for touch panel application

Growing community of inventors

Yunlin County, Taiwan

Shih-Yuan Hsu