Segmented Audio D/A Converter Switching for Higher Mono Gradation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio D/A converters fail to fully utilize hardware resources in mono mode, resulting in suboptimal sound quality due to limited gradation levels and inefficient use of channels.
Innovation Solution
An audio D/A converter switchable between stereo and mono modes, with adjustable gradation levels and distributed output to fully utilize hardware resources, including a first and second segment D/A converter, oversampling filters, multilevel ΔΣ modulators, and switching controllers, allowing for 2×N gradations in mono mode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple channels are formed on one chip for stereo mode, then hardware resources are fully utilized in stereo mode, but hardware resources are not fully utilized in mono mode resulting in limited gradation levels
Solution Approach 1:
The patent implements dynamic switching between stereo and mono modes by controlling the switching means based on mode selection signals. In stereo mode, both first and second segment D/A converters operate independently with N gradations each. In mono mode, the system dynamically reconfigures to combine outputs from both segments, achieving 2×N gradations. This dynamic reconfiguration resolves the contradiction by adapting the system's operation mode to fully utilize hardware resources in both stereo and mono configurations.
Solution Approach 2:
The patent makes the multi-channel D/A converter universal by enabling it to function in both stereo and mono modes using the same hardware resources. The switching means and control logic allow the system to perform different functions (stereo output or mono output with enhanced gradations) based on external mode selection signals. This multi-functionality resolves the contradiction by ensuring that the hardware designed for stereo mode can also deliver superior performance in mono mode.
2Ease of operation
If analog outputs of multiple channels are synthesized in mono mode using conventional methods, then channel synthesis is achieved, but sound quality is suboptimal due to inefficient use of channels
Solution Approach 1:
The patent implements dynamic switching between stereo and mono modes by controlling the switching means based on mode selection signals. In stereo mode, both first and second segment D/A converters operate independently with N gradations each. In mono mode, the system dynamically reconfigures to combine outputs from both segments, achieving 2×N gradations. This dynamic reconfiguration resolves the contradiction by adapting the system's operation mode to fully utilize hardware resources in both stereo and mono configurations.
Solution Approach 2:
The patent merges the outputs of the first and second segment D/A converters in mono mode through the switching means. Instead of using only one segment as in conventional designs, the system combines the analog outputs from both segments, effectively doubling the gradation level from N to 2×N. This merging approach resolves the contradiction by efficiently utilizing all available hardware resources to enhance sound quality in mono mode.
3Device complexity
If N gradations are used in each segment D/A converter, then hardware complexity is reduced, but sound fidelity is limited in mono mode
Solution Approach 1:
The patent merges the outputs of the first and second segment D/A converters in mono mode through the switching means. Instead of using only one segment as in conventional designs, the system combines the analog outputs from both segments, effectively doubling the gradation level from N to 2×N. This merging approach resolves the contradiction by efficiently utilizing all available hardware resources to enhance sound quality in mono mode.
Solution Approach 2:
The patent makes the multi-channel D/A converter universal by enabling it to function in both stereo and mono modes using the same hardware resources. The switching means and control logic allow the system to perform different functions (stereo output or mono output with enhanced gradations) based on external mode selection signals. This multi-functionality resolves the contradiction by ensuring that the hardware designed for stereo mode can also deliver superior performance in mono mode.
Data Source
AI summary
An audio D/A converter includes: a first segment D/A converter including N elements; a second segment D/A converter including N elements; a first oversampling filter configured to process a PCM signal; a second oversampling filter configured to process a PCM signal; a first multilevel ΔΣ modulator configured to process an output of the first oversampling filter; a second multilevel ΔΣ modulator configured to process an output of the second oversampling filter; a first switching controller configured to control the first segment D/A converter according to an input to the first switching controller; and a second switching controller configured to control the second segment D/A converter according to an input to the second switching controller.