Analog-to-digital converter device and capacitance weight correction method

Abstract

An analog-to-digital converter device comprises a capacitor array, a digital logic circuit and a comparator circuit. The capacitor array comprises a plurality of first capacitors, a capacitor to be calibrated and a plurality of compensation capacitors. The digital logic circuit executes a correction program on the capacitor to be corrected so as to correct a weight value of the capacitor to be corrected according to a decision signal, and converts an input signal into a plurality of bits through the capacitor array after executing the correction program. The comparator circuit compares a test signal generated by the first capacitors and the capacitor to be calibrated in response to the calibration program with a predetermined voltage to generate the decision signal. The digital logic circuit further selects at least one of the compensation capacitors according to the weight value so as to adjust the digital code corresponding to the corrected weight value to an integer conforming to the bit expressions.

Description

technical field [0001] The present application relates to analog-to-digital converters, and more particularly to analog-to-digital converters of the approach buffer type with capacitive weight correction. Background technique [0002] Analog-to-digital converters have been widely used in various electronic devices to generate digital signals for subsequent signal processing. In the prior art, various correction mechanisms are used to improve the resolution of the ADC. For example, the digital weight corresponding to the capacitor or the current source is corrected by using a correction mechanism to generate a corresponding digital code. However, in the above technology, if the digital code is not a value expressible by the expected number of digits of the ADC, the resolution of the ADC will decrease. If the number of bits of the analog-to-digital converter is increased in order to express the digital code, the cost of the circuit will be greatly increased. Contents of th...

AI Technical Summary

Problems solved by technology

However, in the above technology, if the digital code is not a value that can be expressed by the expected number of digits of the analog-to-digital converter, the resolution of the analog-to-digital converter will decrease

If the number of digits of the analog-to-digital converter is increased in order to express the digital code, the cost of the circuit will increase significantly

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