Comparator-Tree ADC Architecture for Low-Power Fast Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current analog-to-digital converters face high power consumption due to the large number of comparators required in flash architectures, especially as resolution increases, and existing low-power solutions do not efficiently reduce power consumption while maintaining high speed.
Innovation Solution
A Comparator-based Asynchronous Binary Search (CABS) architecture is introduced, which structures comparators in hierarchical levels, using a self-clocked binary tree with only dynamic comparators and a digital-to-analog converter (DAC) to implement a successive approximation process, reducing the number of active comparators and power consumption by using a binary search instead of parallel search.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If flash architecture is used to achieve high conversion speed, then conversion speed is improved, but power consumption increases exponentially with resolution
Solution Approach 1:
The patent segments the parallel search process into hierarchical levels, where comparators are organized in a tree structure with multiple stages. Instead of all comparators operating simultaneously, the search is divided into sequential stages that activate comparators in a structured manner, reducing the number of active comparators at any given time while maintaining conversion speed through pipelined operation
Solution Approach 2:
The patent introduces dynamic activation of comparators based on the search progress. Comparators are enabled and disabled dynamically during the conversion process, with earlier stages using fewer comparators and later stages activating additional comparators as needed. This dynamic approach allows the system to adapt the number of active comparators to the actual search requirements, significantly reducing average power consumption
2Use of energy by moving object
If the number of comparators is reduced to lower power consumption, then power consumption is improved, but measurement precision may deteriorate
Solution Approach 1:
The patent adds a temporal dimension to the comparison process by using multiple conversion stages. Instead of reducing the number of comparators in a single stage, the system distributes comparisons across multiple time stages, with each stage handling a portion of the total conversion task. This dimensional transformation allows the system to maintain overall precision while using fewer comparators simultaneously
Solution Approach 2:
The patent introduces intermediate digital signals and control logic that coordinate between different comparator stages. These intermediaries manage the sequential activation and deactivation of comparators, ensuring that each comparator is used efficiently and that the overall conversion accuracy is maintained through proper coordination of the hierarchical comparison process
3Speed
If parallel search is used to achieve fast conversion, then conversion speed is improved, but device complexity increases
Solution Approach 1:
The patent segments the complex parallel search architecture into manageable hierarchical stages. Each stage contains a subset of comparators with specific functions, organized in a tree structure that is easier to design, layout, and test than a fully parallel architecture. This segmentation reduces the complexity of individual comparator blocks while maintaining overall conversion speed through coordinated multi-stage operation
Data Source
AI summary
An analog-to-digital converter that uses a comparator based asynchronous binary search is described. The architecture includes a self-clocked (asynchronous) hierarchical binary tree of comparators, each arranged for being provided with a predetermined threshold. The input signal is applied in parallel to all comparators as is the case with flash converters, but the clock is applied to (at least) one comparator only, for example to the first or root comparator. The at least one comparator is further arranged for controlling at least one other comparator of the plurality of comparators.