Patent ID: 7531784
Filing Date: 2009-05-12
Classification: G01J,H01L,H04N

Abstract:
1. A semiconductor device having an illuminance detecting function, comprising: a photoelectric conversion device including a photoelectric conversion element and an amplifier circuit electrically connected to the photoelectric conversion element; and a bias switching unit configured to reverse a bias to be applied to the photoelectric conversion device, wherein the amplifier circuit has two or more transistors including at least a first transistor, wherein a gate electrode of the first transistor is electrically connected to a first electrode of the first transistor through the photoelectric conversion element, wherein the photoelectric conversion element senses incident light, and wherein the bias switching unit switches detection by a current generated in the photoelectric conversion element and detection by a voltage generated in the photoelectric conversion element which is applied between the gate and the first electrode of the first transistor, by reversing the bias at a predetermined level of illuminance.