ADC Feedback Circuit Using Dynamic DAC Elements for Low-Noise Recording
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current recording devices face challenges in achieving low-noise performance due to noise contributions from programmable gain amplifiers (PGA) and analog-to-digital converters (ADC), which increase power consumption and size when gain adjustments are made to improve recording quality.
Innovation Solution
An analog-to-digital conversion circuit with a dynamic range enhancement module that dynamically controls digital-to-analog converters (DAC) elements to adjust gain, eliminating the need for an operational amplifier (OPA) and reducing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If dynamic gain adjustment is implemented by adding PGA and OPA, then recording performance is improved, but power consumption and device size increase significantly
Solution Approach 1:
The patent extracts the gain adjustment function from the traditional PGA-OPA analog path and relocates it to the digital domain. By performing gain adjustment on digital signals after ADC conversion, the system eliminates the need for power-hungry analog amplifiers while maintaining recording performance.
Solution Approach 2:
The patent replaces the mechanical/analog gain adjustment system (PGA and OPA circuits) with a digital signal processing system. Digital gain adjustment through software algorithms substitutes for physical analog components, reducing power consumption and device complexity.
2Ease of operation
If OPA is introduced for gain adjustment, then impedance matching is improved, but power consumption increases
Solution Approach 1:
The patent removes the OPA component from the signal path by transferring the impedance matching function to the digital domain. Digital signal processing handles impedance considerations, eliminating the need for power-consuming operational amplifiers.
3Adaptability or versatility
If multiple components (PGA, OPA) are added for gain control, then signal processing capability is enhanced, but device complexity increases
Solution Approach 1:
The patent extracts gain control and signal processing functions from the analog domain and implements them in the digital domain. This consolidation reduces the number of physical components while maintaining or enhancing processing capabilities through software flexibility.
Solution Approach 2:
The digital signal processing system serves multiple functions simultaneously: gain adjustment, impedance matching, and signal enhancement. A single digital processing unit replaces multiple specialized analog components, reducing overall device complexity.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
An analog-to-digital conversion circuit, a chip, and a recording device are provided. The analog-to-digital conversion circuit includes a main path module, a dynamic range enhancement module, and a dynamic digital-to-analog conversion module. The main path module converts an analog signal and an analog feedback signal into a digital signal to be processed, outputs the digital signal to be processed to the dynamic range enhancement module, and obtains a digital signal output according to the digital signal to be processed and the digital gain signal. The dynamic range enhancement module performs dynamic quantization processing on the digital signal to be processed to obtain at least one control signal and generate the digital gain signal. The dynamic digital-to-analog conversion module dynamically controls on and off of each of DAC elements in a digital-to-analog conversion array according to the at least one control signal and generates the analog feedback signal.