Solid-state image sensing device

摘要

A solid-state image sensing device comprises a pixel which outputs a pixel signal, a first conversion unit which converts the pixel signal into a digital signal with a first bit length, and a second conversion unit which converts, into a digital signal with a second bit length, an analog signal obtained by subtracting, from the pixel signal, an analog signal corresponding to the digital signal with the first bit length. The second conversion unit comprises a current source, a first capacitance, and a switching unit for switching a supply destination of a current supplied from the current source to one of the first capacitance and a reference potential. The second conversion unit performs the conversion based on comparison between a reference voltage and the analog signal which is charged in the first capacitance and is obtained as a subtraction result.

主权项

1. A solid-state image sensing device comprising:
a pixel configured to output a pixel signal; a first conversion unit configured to convert the pixel signal into a digital signal with a first bit length; and a second conversion unit configured to convert, into a digital signal with a second bit length, an analog signal obtained by subtracting, from the pixel signal, an analog signal corresponding to the digital signal with the first bit length, wherein the second conversion unit comprises a current source, a first capacitance, and a switching unit for switching a flow of current supplied from the current source to at least one of the first capacitance and a reference potential, and performs the conversion based on comparison between a reference voltage and the analog signal which is charged in the first capacitance and is obtained as a subtraction result.