US Patent 9503665 Semiconductor integrated circuit and image sensor circuit

The semiconductor integrated circuit includes a first converting circuit that receives the input analog signal, analog-to-digital converts the input analog signal and outputs a resulting first digital signal. The semiconductor integrated circuit includes an amplifier circuit that receives a reference analog signal, which is obtained by the first converting circuit digital-to-analog converting the first digital signal, and the input analog signal and outputs an amplified signal responsive to the difference between the reference analog signal and the input analog signal. The semiconductor integrated circuit includes a second converting circuit that analog-to-digital converts the amplified signal and outputs a resulting second digital signal. The semiconductor integrated circuit includes an output circuit that outputs an output signal obtained by a calculation of the first digital signal and the second digital signal.