Patent ID: 8730078
Filing Date: 2014-05-20
Classification: G01R,H03K,H03M

Abstract:
1. A signal sensing circuit comprising: an analog front-end current sensing circuit for outputting a voltage output based on a current input, the voltage output being associated with a circuit having a first reference impedance; a current source for providing a reference current; a reference voltage generating circuit for generating a high reference voltage and a low reference voltage based on the reference current, wherein the voltage difference between the high and the low reference voltages is associated with a circuit having a second reference impedance, and the circuit having the first reference impedance and the circuit having the second reference impedance are formed by the same material; and an analog-to-digital converter (ADC) for converting the voltage output into a digital output signal based on the reference voltages, where the value of the digital output signal varies with the changes in the current input, and the ratio between the changes in the current input and the changes in the value of the digital output signal is a constant, such that the digital output signal generated based on the current input will not vary with characteristic variations of the material due to temperature and/or moisture.