CPC G09G 3/32 (2013.01) [H03F 3/70 (2013.01); G09G 2310/0291 (2013.01); G09G 2310/0297 (2013.01)] | 20 Claims |
1. An analog front-end for an input sensing device, the analog front-end comprising:
a (1-1)-th charge amplifier including a (1-1)-th input terminal to receive a first sensing signal from a first sensing electrode of the input sensing device and a (1-2)-th input terminal to receive a second sensing signal from a second sensing electrode of the input sensing device, the (1-1)-th charge amplifier is configured to differentially amplify the first sensing signal and the second sensing signal to output a (1-1)-th differential signal;
a (1-2)-th charge amplifier including a (1-3)-th input terminal to receive the second sensing signal from the second sensing electrode and a (1-4)-th input terminal to receive a third sensing signal from a third sensing electrode of the input sensing device, the (1-2)-th charge amplifier configured to differentially amplify the second sensing signal and the third sensing signal to output a (1-2)-th differential signal;
a second charge amplifier including a (2-1)-th input terminal and a (2-2)-th input terminal, the second charge amplifier configured to differentially amplify the (1-1)-th differential signal provided to the (2-1)-th input terminal and the (1-2)-th differential signal provided to the (2-2)-th input terminal and output a (2-1)-th differential signal and a (2-2)-th differential signal;
a demodulation circuit configured to filter the (2-1)-th differential signal and the (2-2)-th differential signal and output demodulated differential signals, and
an analog-to-digital converter configured to output a sensing value based on the demodulated differential signals.
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