Voltage monitoring circuit and voltage monitoring method

A voltage monitoring circuit, comprising:

• a first multiplexer having a plurality of input terminals, an output terminal and a control terminal, with each of the plurality of input terminals of the first multiplexer receiving a respective one of a plurality of first subject voltages;
• a controller electrically connected to the control terminal of the first multiplexer, with the controller controlling, through the control terminal of the first multiplexer, the first multiplexer to output one of the plurality of first subject voltages from the output terminal of the first multiplexer, the controller generating a testing signal comprising a plurality of electric potentials, the controller having a port configured to output the plurality of electric potentials switching according to a switching command of the controller;
• a resistor-network circuit comprising a plurality of first resistors, with one terminal of each of the plurality of first resistors connected to the controller for receiving a respective one of the plurality of electric potentials of the testing signal, the resistor-network circuit configured to sequentially generate a plurality of first reference voltages according to switches of the plurality of electric potentials;
• and
• a first comparison circuit having a first input terminal, a second input terminal and an output terminal, with the first input terminal of the first comparison circuit electrically connected to the output terminal of the first multiplexer, the second input terminal of the first comparison circuit electrically connected to the resistor-network circuit, the first comparison circuit configured to sequentially compare each of the plurality of first reference voltages to the first subject voltage outputted from the first multiplexer for sequentially outputting a plurality of first comparison results, the first comparison circuit configured to sequentially send the plurality of first comparison results to the controller through the output terminal of the first comparison circuit for determining a voltage value of the first subject voltage, wherein each of the plurality of first comparison results has electric potential information.