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

Claim 1:
2. The AD converter with self-calibration function according to claim 1, wherein the summation and conversion unit comprises:
a switching section that connects, to a capacitance holding the unit voltage, the input voltage during conversion and either the reference voltage or a ground voltage at the time of calibration;
a summation section that, during conversion, makes the input voltage be held in the capacitance and thereafter sums any one of the two or more unit voltages to the voltage being held to generate a summed voltage, and at the time of calibration, makes the reference voltage or the ground voltage be held in the capacitance and thereafter sums any one of the two or more unit voltages to the voltage being held to generate a summed voltage;
a cross-bar switch that switches between a case where the reference voltage is output to one output end and the summed voltage is output to another output end, and a case where the reference voltage is output to the other output end and the summed voltage is output to the one output end; and
the comparator that outputs a comparison signal when a voltage at a positive input end exceeds a voltage at a negative input end while the one output end being connected with the negative input end and the other output end being connected with the positive input end.