ANALOG-TO-DIGITAL CONVERTER APPLICABLE TO A SOLID STATE IMAGE PICKUP DEVICE, AN ANALOG-TO-DIGITAL CONVERTING METHOD, A SOLID STATE IMAGE PICKUP DEVICE, AND A CAMERA SYSTEM

摘要

PURPOSE: An analog-to-digital converter, an analog-to-digital converting method, a solid state image pickup device, and a camera system are provided to expand a dynamic range with high precision without depending on overflow of an AD range.;CONSTITUTION: A comparator(210) compares a reference signal with an input signal. The comparator inverts output if the reference signal and the input signal are matched. The counter counts a comparison time of the comparator. A control circuit(230) monitors output of the comparator. A voltage generating circuit generates a direct current voltage according to a monitor result when a monitor result of the control circuit is a level in which output of the comparator is preset. An analog adder adds a voltage generated by the voltage generating circuit to an input signal. The analog adder supplies a voltage to an input terminal of the comparator.;COPYRIGHT KIPO 2010