Patent ID: 8269873

Claim:
A solid-state imaging device comprising: a plurality of pixel circuits each of which converts an optical signal into a pixel signal; a load current source circuit adapted to supply a load current, used to read out the pixel signal from the plurality of pixel circuits, to the pixel circuits on a column-by-column basis; a signal readout circuit adapted to read out a reference signal and the pixel signal from the pixel circuits on a row-by-row basis and output the difference between the reference and pixel signals that have been read out; and a control signal generation circuit adapted to generate a maintenance control signal used to maintain the load current constant during a readout period that lasts from when the reference signal is read out by the signal readout circuit to when the pixel signal is read out by the signal readout circuit, wherein the load current source circuit includes a plurality of load transistors adapted to supply the load current to the pixel circuits on a column-by-column basis, a voltage holding circuit adapted to stabilize the gate voltages of the load transistors so as to maintain the load current constant, and a voltage setting circuit adapted to set the voltage holding circuit to a constant hold voltage based on the maintenance control signal.