Signal processing circuit and method with pressure-sensitive sensor array
A signal processing circuit with a pressure-sensitive sensor array includes a pressure-sensitive sensor array with M rows and N columns, and an excitation source adapted for outputting positive and negative excitation voltages, wherein: the positive output terminals of the sensing units at a same row of the pressure-sensitive sensor array are connected with each other and act as an output of the row; the negative output terminals of the sensing units at a same column of the pressure-sensitive sensor array are connected with each other and act as an output of the column; so that the whole pressure-sensitive sensor array has a positive excitation input end, a negative excitation input end, M row output signals and N column output signals. The signal processing circuit and method are capable of significantly decreasing an amount of output signal wires of the sensor, reducing connection areas, and improving reliability.
1. A signal processing circuit with a pressure-sensitive sensor array comprising: a pressure-sensitive sensor array with M rows and N columns, an excitation source adapted for outputting positive and negative excitation voltages, and an analog-digital convert circuit, wherein:
the pressure-sensitive sensor array comprises M×N sensing units which are connected with each other through a bridge manner, wherein every sensing unit has a positive excitation input terminal, a negative excitation input terminal, a positive output terminal and a negative output terminal, the positive excitation input terminal of every sensing unit is connected with the positive excitation voltage, the negative excitation input terminal of every sensing unit is connected with the negative excitation voltage;
the positive output terminals of the sensing units at a same row of the pressure-sensitive sensor array are connected with each other and act as an output of the row;
the negative output terminals of the sensing units at a same column of the pressure-sensitive sensor array are connected with each other and act as an output of the column;
the whole pressure-sensitive sensor array has a positive excitation input end, a negative excitation input end, M row output signals and N column output signals;
the analog-digital convert circuit comprises at least one analog-digital converter for converting the row and column output signals of the sensor array to digital signals;
the signal processing circuit further comprises a pseudo half-bridge circuit which has a positive excitation input end and a negative excitation input end respectively connected with the positive and negative excitation voltages; wherein the pseudo half-bridge circuit has an output signal which is determined by the positive and negative excitation voltages of the excitation source; any one of the row and column output signals and the output signal of the pseudo half-bridge circuit form a signal pair to be sent to the analog-digital convert circuit for conversion.