Differential Signal Acquisition Using TFT Light-Sensing Pixel Array

Differential signal acquisition is suitable for tiny signal sensing applications. By eliminating background offset impact, it optimizes sensing accuracy. In this article, we propose the differential sensing pixel circuit. The circuit can separate the common and differential signals, which are usually in a very distinct range. Thus, the signals can be amplified, respectively, in gain. The function of the circuit is verified using HSPICE simulation. Moreover, the issues of array arrangement are also considered. In addition, we use discrete components to build the circuit for verification. The feature of differential signal acquisition can be very useful in the application of optical under-screen fingerprint recognition.