Patent ID: 7372489
Filing Date: 2008-05-13
Classification: H04N

Abstract:
1. A signal processing circuit comprising: a plurality of VI conversion circuits, including each one resistor, converting an input voltage to a current based on the resistance value of said resistor, and outputting this current from an output terminal; an IV conversion circuit, inputting, into an input terminal, the current output from said output terminal of said VI conversion circuit, converting this current to a voltage, and outputting this voltage; and a selection circuit, successively selecting each of said output terminals of a plurality of said VI conversion circuits and connecting the selected output terminal to said input terminal of said IV conversion circuit, wherein said VI conversion circuit comprises: an amp, having a first input terminal, a second input terminal, and an output terminal, and inputting said input voltage into said first input terminal and outputting, from said output terminal, a voltage corresponding to the difference in the respective potentials of said first input terminal and said second input terminal; a MOS transistor, having a gate terminal, source terminal, and a drain terminal, said gate terminal being connected to said output terminal of said amp; a resistor, one end of which is connected to said second input terminal of said amp and to said source terminal of said MOS transistor and the other end of which is connected to a first reference potential; and a switch, one end of which is connected to said drain terminal of said MOS transistor and the other end of which is set to a second reference potential; and converts said input voltage to a current and outputs this current from said drain terminal of said MOS transistor.