Hybrid DAC Direct Digital Synthesizer for Low-Power Phase Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Direct digital frequency synthesizers face challenges with complex configuration, high power consumption, and low integration due to the need for large pipelines and complicated operators in phase-to-amplitude mapping, which limits their application range and increases costs.
Innovation Solution
A direct digital frequency synthesizer using a hybrid digital-to-analog converter with a non-linear DAC and a linear DAC, where the non-linear DAC generates base point currents and the linear DAC generates gradient currents for linear approximation, simplifying the configuration and eliminating the need for summing base points and gradients, thereby reducing complexity and power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a direct digital frequency synthesizer uses traditional phase-to-amplitude mapping methods (ROM, Taylor series, CORDIC), then frequency synthesis precision is maintained, but device complexity and power consumption increase significantly
Solution Approach 1:
The patent divides the phase-to-amplitude mapping process into two independent segments: a non-linear mapping unit that handles the complex non-linear transformation, and a linear interpolation unit that performs simple linear approximation. This segmentation allows each unit to be optimized independently, reducing overall device complexity while maintaining synthesis precision through the combination of both segments.
2Measurement precision
If a direct digital frequency synthesizer uses traditional phase-to-amplitude mapping methods (ROM, Taylor series, CORDIC), then frequency synthesis precision is maintained, but power consumption increases due to complicated operations
Solution Approach 1:
The patent segments the computational workload into a non-linear mapping unit that pre-calculates and stores mapping relationships, and a linear interpolation unit that performs computationally simple linear approximation. This segmentation dramatically reduces the real-time computational power required while maintaining precision, as the complex non-linear operations are pre-computed and stored rather than calculated in real-time.
Solution Approach 2:
The non-linear mapping unit performs the complex non-linear mapping operations in advance and stores the results, so that during frequency synthesis only simple linear interpolation is needed. This preliminary action transfers the computational burden from real-time operation to pre-processing, significantly reducing power consumption during actual frequency synthesis operations.
3Measurement precision
If a direct digital frequency synthesizer uses large pipelines and complicated operators for base point and gradient summation, then output resolution is improved, but integration efficiency decreases and device size increases
Solution Approach 1:
The patent extracts and eliminates the complex base point and gradient summation operators from the frequency synthesis path. Instead of using traditional methods that require large pipelines and complicated summation logic, the invention uses a simplified non-linear mapping unit followed by linear interpolation, which achieves the same output resolution without requiring complex operators or large pipeline structures, thereby improving integration efficiency.
Data Source
AI summary
A direct digital frequency synthesizer and a synthesizing method thereof. The direct digital frequency synthesizer uses a hybrid digital to analog converter, which matches output data of a phase accumulator to a sine wave amplitude using a hybrid DAC, including a non-linear DAC and a linear DAC. The non-linear DAC outputs a direct base point current using some bits of output data of a phase accumulator, causing the linear DAC to output a gradient current based on gradient information generated using other bits of the output data of the phase accumulator. These currents are summed for the analog output.