US 11,735,103 B2
Input sensing device having an analog front-end
Kyung Tea Park, Yongin-si (KR); Ji Woong Kim, Yongin-si (KR); Hyung Gun Ma, Yongin-si (KR); Seong An Park, Yongin-si (KR); Seong Joo Lee, Yongin-si (KR); Tae Hun Lee, Yongin-si (KR); and Sang Hyun Heo, Yongin-si (KR)
Assigned to SAMSUNG DISPLAY CO., LTD., Yongin-si (KR)
Filed by SAMSUNG DISPLAY CO., LTD., Yongin-si (KR)
Filed on Apr. 15, 2022, as Appl. No. 17/721,465.
Claims priority of application No. 10-2021-0116567 (KR), filed on Sep. 1, 2021.
Prior Publication US 2023/0061354 A1, Mar. 2, 2023
Int. Cl. G09G 3/32 (2016.01); H03F 3/70 (2006.01)
CPC G09G 3/32 (2013.01) [H03F 3/70 (2013.01); G09G 2310/0291 (2013.01); G09G 2310/0297 (2013.01)] 20 Claims
OG exemplary drawing
 
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.