Audio Reproduction LSI Fading Control for Smooth Pitch and Volume Shifts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio reproduction devices in electric vehicles experience unnatural fading sounds during pitch or volume adjustments due to the need for frequent register setting updates, leading to irregular timing and smoothness issues.
Innovation Solution
The audio reproduction device incorporates a pitch register, volume register, and fading register to store setting values, allowing for staged changes in frequency and volume through a reproduction control part that executes these changes based on step setting values from the fading register, minimizing external access and ensuring regular timing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the host microcomputer frequently updates the register setting values to achieve smooth fading, then the fading smoothness improves, but the processing time and complexity increase
Solution Approach 1:
The audio reproduction LSI pre-calculates and stores fading setting values in a fading memory at regular time intervals before fading is needed. When fading is initiated, these pre-calculated values are automatically read and applied, eliminating the need for real-time calculation and ensuring both smooth transitions and regular timing without processing delays
Solution Approach 2:
The audio reproduction LSI autonomously manages the fading process by automatically reading pre-stored setting values from its internal fading memory and applying them to the pitch or volume registers without requiring continuous external intervention from the host microcomputer, thereby achieving regular timing and smooth transitions
2Measurement precision
If the host microcomputer accesses the register frequently to change setting values, then the fading control precision improves, but the device complexity and processing overhead increase
Solution Approach 1:
The fading control function is extracted from the host microcomputer and implemented as an autonomous feature within the audio reproduction LSI. The LSI maintains an internal fading memory and control logic that independently manages pitch and volume fading, reducing the communication burden on the host microcomputer while maintaining precise fading control
Solution Approach 2:
A fading memory within the audio reproduction LSI serves as an intermediary structure that stores pre-calculated fading setting values. This intermediary allows the system to achieve precise fading control through automatic reading of predetermined values without requiring frequent direct host microcomputer access or complex real-time calculations
Data Source
AI summary
An audio reproduction device includes a reproduction control part executing pitch fading processing of changing a frequency of audio during reproduction in stages or volume fading processing of changing a sound volume in stages, a pitch register storing a pitch setting value, a volume register storing a volume setting value, and a fading register storing a step setting value indicating a form of change in the pitch or volume fading processing. The reproduction control part changes the frequency in stages in a form based on the step setting value in response to change of the pitch setting value while having a pitch setting value after change as a target value, and changes the sound volume in stages in a form based on the step setting value in response to change of the volume setting value while having a volume setting value after change as a target value.