Device and method for calibrating capacitor array type successive-approximation analog-to-digital converter

Abstract

The invention relates to a device and method for calibrating a capacitor array type successive-approximation analog-to-digital converter, which belong to the field of mixed-signal integrated circuit design; the device comprises a capacitance measurement circuit, a static memory, a control circuit corresponding to the static memory, and a logical operation unit connected between the capacitance measurement circuit and the static memory; and the method comprises the following steps: measuring the true values of each pair of capacitors in a capacitor array to be calibrated by using the capacitance measurement circuit; according to the actual structure of the capacitor array, calculating the true weight values of each pair of capacitors according to the measured true values by using the logical operation unit, mapping the weight values into n-bit binary weight codes, and storing the binary weight codes into the static memory so as to form a final weight code table; and carrying out corresponding correction on the output codes of the analog-to-digital converter to be calibrated by using the final weight code table so as to obtain the finally-calibrated output codes. The device and method provided by the invention have the advantages in the aspects of hardware cost and conversion rate.

Description

technical field

[0001] The invention belongs to the field of mixed-signal integrated circuit design, and particularly relates to a calibrating method of a capacitance array type successive approximation analog-to-digital converter, which can compensate capacitance mismatch caused by process deviation. Background technique

[0002] With the development of the information industry, the digital signal processing technology is changing with each passing day, and the analog-to-digital / digital-to-analog (A / D, D / A) converter as a bridge connecting the analog and digital worlds has also been more and more widely used. With the improvement of digital signal processing speed, it will inevitably put forward high-speed and high-precision requirements for analog-to-digital / digital-analog converters; at the same time, the vigorous development of portable consumer electronics and medical equipment also requires analog-to-digital / digital-analog converters. requirements for low power consump...

Examples

Embodiment Construction

[0021] The present invention proposes a calibrating device and method for a capacitance array type successive approximation analog-to-digital converter, combined below Image 6 and Figure 7 Describe the working process of the device in detail.

[0022] The calibrating device of a kind of capacitance array type successive approximation analog-to-digital converter that the present invention proposes (see Image 6The part marked with a dotted line box) includes a capacitance measurement circuit C-M, a static memory SRAM and a corresponding control circuit; on this basis, a logical operation unit ALU connected between the capacitance measurement circuit and the static memory is added; Image 6 Outside the dotted line box is shown the capacitor array successive approximation analog to digital converter to be calibrated which is composed of capacitor array digital to analog converter, bias clock circuit, comparator CMP and successive approximation logic SAR-Logic.

[0023] The sp...

technical field

[0001] The invention belongs to the field of mixed-signal integrated circuit design, and particularly relates to a calibrating method of a capacitance array type successive approximation analog-to-digital converter, which can compensate capacitance mismatch caused by process deviation. Background technique

[0002] With the development of the information industry, the digital signal processing technology is changing with each passing day, and the analog-to-digital / digital-to-analog (A / D, D / A) converter as a bridge connecting the analog and digital worlds has also been more and more widely used. With the improvement of digital signal processing speed, it will inevitably put forward high-speed and high-precision requirements for analog-to-digital / digital-analog converters; at the same time, the vigorous development of portable consumer electronics and medical equipment also requires analog-to-digital / digital-analog converters. requirements for low power consump...

Examples

Embodiment Construction

[0021] The present invention proposes a calibrating device and method for a capacitance array type successive approximation analog-to-digital converter, combined below Image 6 and Figure 7 Describe the working process of the device in detail.

[0022] The calibrating device of a kind of capacitance array type successive approximation analog-to-digital converter that the present invention proposes (see Image 6The part marked with a dotted line box) includes a capacitance measurement circuit C-M, a static memory SRAM and a corresponding control circuit; on this basis, a logical operation unit ALU connected between the capacitance measurement circuit and the static memory is added; Image 6 Outside the dotted line box is shown the capacitor array successive approximation analog to digital converter to be calibrated which is composed of capacitor array digital to analog converter, bias clock circuit, comparator CMP and successive approximation logic SAR-Logic.

[0023] The sp...

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