Readout Circuit Based on Differential Offset Cancellation Technique for Projected Mutual-Capacitance Large Touch Screens
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This paper proposes an efficient method to improve the performance of the projected mutual capacitance large touch screen panels (TSPs) based on differential offset cancellation technique. To achieve high scan rate the proposed architecture uses concurrent and continuous sine waves as driving technique. In contrast to the conventional offset compensation topologies cannot handle such a concurrent or continuous signals properly, however, the proposed architecture overcomes such switching noise. In addition to, it provides an effective noise cancellation for such signals. The proposed architecture has been implemented using a Magnachip/SK Hynix 0.18 µm CMOS process. However, the measured results show a 14 dB improvement I SNR compared to conventional architectures. Also, the proposed readout circuit shows a good performance after mismatch condition applied to input stage of the differential amplifier to show the effectiveness of the proposed cancellation technique.
Abstract
This paper proposes an efficient method to improve the performance of the projected mutual capacitance large touch screen panels (TSPs) based on differential offset cancellation technique. To achieve high scan rate the proposed architecture uses concurrent and continuous sine waves as driving technique. In contrast to the conventional offset compensation topologies cannot handle such a concurrent or continuous signals properly, however, the proposed architecture overcomes such switching noise. In addition to, it provides an effective noise cancellation for such signals. The proposed architecture has been implemented using a Magnachip/SK Hynix 0.18 µm CMOS process. However, the measured results show a 14 dB improvement I SNR compared to conventional architectures. Also, the proposed readout circuit shows a good performance after mismatch condition applied to input stage of the differential amplifier to show the effectiveness of the proposed cancellation technique.
참고문헌 (13)
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