US 2014/0152482 A1 · COMPARATOR AND CORRECTION METHOD THEREFOR

Abstract

A comparator has a comparator circuit to output an output voltage based on a voltage difference between a first and second input voltage, a variable capacitor connected to an output terminal, an input voltage control circuit to generate a common voltage and add the common voltage to the first and the second input voltages, and a correction circuit to control the variable capacitor to control the common voltage. The correction circuit controls a first capacitance value of the variable capacitor so that the output voltage is reversed when the voltage difference equals a first voltage difference, and controls a second capacitance value of the variable capacitor so that the output voltage is reversed when the voltage difference equals a second voltage value, and controls the common voltage so that a difference between the first capacitance value and the second capacitance value becomes equal to a predetermined capacitance value.

Claims15

Dependent claims

A comparator comprising:

a comparator circuit configured to output to an output terminal an output voltage based on a voltage difference between a first input voltage which is input to a first input terminal and a second input voltage which is input to a second input terminal;
a variable capacitor connected to the output terminal;
an input voltage control circuit configured to generate a common voltage to be added to the first and the second input voltages, to generate the first and the second input voltages including a differential voltage generated according to the common voltage;
and
a correction circuit configured to control the variable capacitor to control the common voltage,
wherein the correction circuit controls a first capacitance value of the variable capacitor so that the potential of the output voltage is reversed when the voltage difference equals a first voltage difference, and controls a second capacitance value of the variable capacitor so that the potential of the output voltage is reversed when the voltage difference equals a second voltage value which is different from the first voltage difference by a predetermined voltage value, and controls the common voltage so that a difference between the first capacitance value and the second capacitance value becomes equal to a predetermined capacitance value.

3 more elements

A correction method for a comparator circuit of which output terminal is connected to a variable capacitor and which is configured to output to an output terminal an output voltage based on a voltage difference between a first input voltage which is input to a first input terminal and a second voltage which is input to a second input terminal, the correction method comprising:

controlling a capacitance value of the variable capacitor;
controlling a common voltage to be added to the first and the second input voltages;
generating the first and the second input voltages including a differential voltage generated according to the common voltage;
and
performing a common voltage controlling to control a first capacitance value of the variable capacitor so that the potential of the output voltage is reversed when the voltage difference equals the first voltage difference, to control a second capacitance value of the variable capacitor so that the potential of the output voltage is reversed when the voltage difference equals a second voltage difference which is different from the first voltage difference by a predetermined voltage value, and to control the common voltage so that a difference between the first capacitance value and the second capacitance value becomes equal to a predetermined capacitance value.

2 more elements

Dependencies are inferred from the claim text.

Comparator and correction method therefor

Life of this patent

Comparator and correction method therefor

Life of this patent

Abstract

Claims15