ANALOG-TO-DIGITAL CONVERTER AND ANALOG-TO-DIGITAL CONVERTING METHOD

摘要

An embodiment of the present invention relates to an analog-to-digital converter which converts an analog input voltage into an output digital code of N bits. Disclosed is the analog-to-digital converter comprising: a successive approximation conversion unit which receives an analog input voltage and a first reference voltage, determines a level of a voltage of a first node to be a negative level of the analog input voltage through a sampling operation and a holding operation, and determines an output logic value corresponding to one bit of an output digital code of N bits for each successive approximation cycle by using a successive approximation method while adjusting the level of the voltage of the first node based on a level of the first reference voltage; a voltage comparison unit which generates a comparison logic value by comparing the level of the voltage of the first node with a level of a second reference voltage; and a control unit which, when the output logic value or comparison logic value satisfies a specific condition, terminates an analog-to-digital conversion process using the successive approximation method, and determines the output digital code of N bits.