Patent ID: 11936396
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Measurement (Instruments)
Classification: CPC H  G | IPC H

Claim 3:
4. The AD converter with self-calibration function according to claim 2,
wherein the summation section comprises:
a coarse adjustment positive unit voltage having a largest absolute value among the unit voltages;
a fine adjustment positive unit voltage having a smaller absolute value than the coarse adjustment positive unit voltage; and
a difference computation portion that charges the capacitance with a voltage equal to a difference between the input voltage and a predetermined base voltage generated by a base voltage portion, and
wherein the calibration control section comprises:
a difference voltage measurement processing portion that, when a summed voltage resulting from summation of the coarse adjustment positive unit voltage exceeds a voltage equal to a sum of the reference voltage and the offset voltage of the comparator, performs summation of the summed voltage further with the fine adjustment positive unit voltage.