Patent attributes
An analog-to-digital converter with calibration is provided. The converter includes at least one conversion unit. The conversion unit includes a comparator, a control unit, a count unit, and a calibration unit. The comparator compares the voltage of the first input terminal with the voltage of the second input terminal and outputs a comparison result. The control unit outputs a control signal according to a comparison result of the comparator and a selecting signal. The count unit performs a count operation according to the control signal and outputs a count result. The calibration unit provides a reference voltage to the second input terminal of the comparator, and adjusts the level of the reference voltage according to the count result of the count unit. Thus, reference voltage is included inside each conversion unit and conventional resistor ladder producing reference voltage can be removed.