VOLTAGE CALIBRATION CIRCUIT CAPABLE OF UPDATING VOLTAGE TO BE CALIBRATED AUTOMATICALLY

摘要

A voltage calibration circuit includes a voltage output circuit, an amplifier, a notification circuit, and a built-in self-test circuit. The voltage output circuit selects a first voltage source to output an output voltage according to a selection signal. Two input terminals of the amplifier are for receiving the output voltage and a reference voltage corresponding to the first voltage source respectively. The notification circuit outputs a notification signal according to the reference voltage, a voltage at an output terminal of the amplifier and an indication voltage. The indication voltage and the output voltage have a fixed voltage difference. The built-in self-test circuit updates the selection signal according to the notification signal so that the voltage output circuit can select a second voltage source accordingly.

主权项

1. A voltage calibration circuit, comprising:
a voltage output circuit comprising a plurality of voltage sources to be calibrated, and configured to select a first voltage source from the plurality of voltage sources to output an output voltage to be calibrated according to a selection signal; a first amplifier having a first input terminal configured to receive the output voltage, a second input terminal configured to receive a reference voltage corresponding to the first voltage source, and an output terminal; a notification circuit coupled to the output terminal of the first amplifier, and configured to output a notification signal according to an indication voltage, the reference voltage, and a voltage at the output terminal of the first amplifier, wherein the indication voltage and the output voltage have a first fixed voltage difference; and a built-in self-test circuit coupled to the notification circuit, the first amplifier, and the voltage output circuit, and configured to update the selection signal according to the notification signal so as to enable the voltage output circuit to select a second voltage source from the plurality of voltage sources accordingly.