US 12,443,304 B1
Capacitive sensing circuit, system, and device thereof
Xingbo Ding, Kunshan (CN)
Assigned to Kunshan Yunyinggu Electronic Technology Co., Ltd., Kunshan (CN)
Filed by Kunshan Yunyinggu Electronic Technology Co., Ltd., Kunshan (CN)
Filed on Jan. 10, 2025, as Appl. No. 19/016,182.
Application 19/016,182 is a continuation of application No. PCT/CN2024/142947, filed on Dec. 27, 2024.
Int. Cl. G06F 3/041 (2006.01); G06F 3/044 (2006.01)
CPC G06F 3/0416 (2013.01) [G06F 3/0446 (2019.05)] 20 Claims
OG exemplary drawing
 
1. A circuit for capacitive sensing, comprising:
a current mirror circuit configured to receive two input current signals associated with two respective capacitance values and send two mirrored current signals;
a current-differential current-summing circuit configured to receive the two mirrored current signals from the current mirror circuit and send a current-differential signal and a current-summing signal;
a transconductor circuit comprising a transconductor, wherein the transconductor circuit is configured to receive the current-differential signal and send a feedback current; and
a clamping circuit configured to receive the feedback current and minimize a difference between two voltages of two respective nodes of the current mirror circuit.