Highly parallel touch controller with high-speed weighted median noise reduction unit for on-cell type touch screen panel

Projected capacitive type touch panels are widely used in smart devices. This paper proposes a highly parallel touch controller for a large-sized on-cell type projected capacitive touch panel. The proposed novel hardware architecture use a weighted median filtering algorithm as a noise reduction unit. The proposed novel weighted median hardware architecture is compact and power efficient. The proposed parallel processing architecture is very fast as it processes three touch algorithms in parallel manner. According to the synthesis, simulation, and power analysis results, the proposed touch controller unit added consumed power of only 818 μW and 213 Hz of touch report rate with 36 dB touch Signal to Noise Ratio (SNR).