Recursive Switched DAC Circuit for Display Resolution Scaling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional digital-to-analog converters in display devices face challenges with increasing resolution, as the number of elements increases, leading to mismatches that affect performance and require more components, which is inefficient.
Innovation Solution
A digital-to-analog converter design incorporating a multiplexer and a recursive switched circuit that alternately receives input and reference voltages, using capacitors and switch blocks controlled by a square wave signal to output an average voltage, reducing the impact of capacitor mismatches and minimizing the number of elements needed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the resolution of the display device increases, then the number of bits of the digital image signal increases, but the number of elements of the digital-to-analog converter increases and element mismatch effects worsen
Solution Approach 1:
The digital-to-analog converter is divided into multiple independent conversion units, each handling a portion of the digital signal bits. This segmentation allows the system to process high-resolution signals without requiring a single large complex converter, thereby reducing element mismatch effects while maintaining high conversion precision.
Solution Approach 2:
The patent employs dynamic switching mechanisms that alternately connect different capacitor groups to the conversion circuit based on the input signal requirements. This dynamic reconfiguration allows the same hardware elements to serve multiple functions across different bit positions, reducing the total number of elements needed while maintaining high-resolution conversion capability.
2Measurement precision
If the number of bits of the digital image signal increases, then the conversion precision improves, but the capacitance of elements and the number of elements increase
Solution Approach 1:
The capacitor groups are designed to serve multiple bit positions through dynamic switching. The same capacitors are reused across different conversion units by alternating their connections, making them multi-functional elements. This universality reduces the total quantity of capacitors needed while maintaining the precision required for high-bit digital-to-analog conversion.
Solution Approach 2:
The patent changes the connection parameters (switching states) of the capacitor groups dynamically based on which bit is being converted. By altering the electrical configuration parameters rather than adding more physical elements, the system achieves high conversion precision for increased bit depths without proportionally increasing the number of capacitors.
3Measurement precision
If more elements are used to handle increased bit depth, then the conversion accuracy is maintained, but the device complexity and element mismatch increase
Solution Approach 1:
The conversion system is segmented into multiple independent units, each with its own capacitor group. This segmentation isolates mismatch errors to individual units rather than propagating them across the entire system. Each segment processes a portion of the bits independently, maintaining overall conversion accuracy while reducing the impact of element mismatches.
Solution Approach 2:
The patent employs periodic switching between different capacitor groups in an alternating pattern. This periodic action allows the system to distribute the conversion workload across multiple capacitor sets over time, reducing the sensitivity to mismatches in any single capacitor while maintaining high conversion accuracy through the alternating measurement and computation cycles.
Data Source
AI summary
A digital-to-analog converter having a structure that converter may decrease an effect of a mismatch between elements and decrease a quantity of the elements. The digital-to-analog converter includes a multiplexer configured to output a first voltage or a second voltage corresponding to an input bit as an input voltage and a recursive switched circuit configured to alternately receive the input voltage and a reference voltage and to output an average value of the input voltage and the reference voltage as an output voltage.