SAR ADC Noise Estimation for Higher Resolution Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current analog-to-digital converters face limitations in resolution due to insufficient noise information from simulations, as they fail to accurately represent real noise environments, including intrinsic and electromagnetic interference, leading to inadequate improvement in resolution.
Innovation Solution
A successive approximation register analog-to-digital converter with a sampling circuitry, comparator circuitry, and controller circuitry that generates decision signals and performs statistical calculations to estimate noise values, allowing for improved noise representation and resolution enhancement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If simulation is employed to estimate noise information, then noise information about certain circuits can be obtained, but the noise information is insufficient to represent real noise information including intrinsic noises and electromagnetic interference
Solution Approach 1:
The patent employs feedback by measuring actual noise from the converter output and using it to adjust the dither signal generation. The measured noise characteristics feed back into the system to refine the dither signal, creating a closed-loop system that continuously improves noise representation accuracy.
Solution Approach 2:
The system uses itself to generate the required noise information by measuring its own output noise characteristics. The converter measures its own noise performance and uses this self-measured data to generate appropriate dither signals, eliminating the need for external simulation or separate measurement equipment.
2Measurement precision
If predetermined calculation is performed according to noise information to increase resolution, then resolution improvement is attempted, but the resolution is not improved significantly due to insufficient noise information
Solution Approach 1:
The system performs preliminary measurement of noise characteristics during an initial calibration phase before actual conversion operations. This preliminary action captures the actual noise environment, which is then stored and used to guide subsequent conversion operations with appropriate dither signals applied.
Solution Approach 2:
The patent changes the dither signal parameters (amplitude, frequency, waveform) based on the measured noise characteristics. By adjusting these parameters to match the actual noise environment, the system optimizes the effectiveness of noise shaping and filtering, thereby improving resolution.
3Measurement precision
If statistical calculation is performed to obtain statistical noise value, then practical noise estimation is improved, but additional processing steps are required
Solution Approach 1:
The patent extracts only the essential statistical parameters (mean, variance) from the measured noise signal, rather than processing the entire noise waveform. This extraction approach captures the critical noise characteristics needed for dither signal generation while minimizing computational complexity.
Solution Approach 2:
The system uses a simple moving average filter for statistical calculation rather than complex statistical analysis. This lightweight approach provides sufficient accuracy for noise estimation without requiring substantial computational resources or complex circuitry.
Data Source
AI summary
A successive approximation register analog to digital converter includes a sampling circuitry, a comparator circuit, and a controller circuitry. The sampling circuitry generates first and second signals according to a sampled signal. The comparator circuit compares the first signal with the second signal to generate first decision signals. The controller circuitry generates digital codes according to the first decision signals, and controls the comparator circuit to perform comparisons repeatedly to generate second decision signals, in order to generate a digital output according to the digital codes, a statistical noise value, and the second decision signals. The controller circuitry further controls the sampling circuitry and the comparator circuit to perform comparisons repeatedly according to the sampled signal having an initial level during an initial phase, in order to generate third decision signals, and performs a statistical calculation to obtain the statistical noise value according to the third decision signals.