Common mode suppression fingerprint sensing device

摘要

The present invention relates to a fingerprint sensing device for sensing a fingerprint pattern of a finger, the fingerprint sensing device including at least first and second sensing structures and at least first and second charge amplifiers. Each charge amplifier includes a first input, a second input, an output, and at least one amplifier stage between the first and second inputs and the output. The output is capacitively coupled to the first input. The first input of the first charge amplifier is connected to the first sensing structure, the first input of the second charge amplifier is connected to the second sensing structure, and the output of the first charge amplifier is the second Are capacitively coupled to the first input of the charge amplifier to suppress the in-phase component. [Selection] Figure 7