Patent ID: 7123302

Claim:
A semiconductor device that photographs images and outputs digital image data, the semiconductor device comprising: an area sensor including a plurality of image sensors, each of which outputs an analog image signal corresponding to an amount of received light; and an A/D conversion section that includes: a first circuit that outputs a numerical value ranging from an initial value to a final value, a second circuit that outputs a signal having a potential which rises in a polygonal line, the potential rising according to a first linear rise as the numerical value changes from the initial value toward a first intermediate value, according to a second linear rise as the numerical value changes from the first intermediate value to a second intermediate value, and according to a third linear rise as the numerical value changes from the second intermediate value to the final value, the third linear rise being greater than the second linear rise, and the second linear rise being greater than the first linear rise, a third circuit that compares the analog image signal and the signal output from the second circuit and outputs a comparative signal, and a fourth circuit that outputs the numerical value as digital image data according to the comparative signal.