Digital Microphone Signal Switching to Eliminate Audio Popping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Digital signal generation devices, such as digital microphones, produce unstable signals during switching processes, leading to issues like audio popping, which affect user experience.
Innovation Solution
A signal processing system and method that includes a mode selection element, switching element, and power element, utilizing a first delay element to switch to a virtual signal before turning off the digital source, and a power element to stop outputting voltage based on a delay signal reaching a specific voltage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a physical switch is used to stop or start the digital signal generation device, then the device can be controlled to turn on/off, but unstable signals are generated during switching causing audio popping
Solution Approach 1:
The patent applies preliminary action by switching the output signal to a virtual signal source before the digital microphone is actually turned off. The mode selection element receives the turn-off signal and outputs a first signal that triggers the switching element to switch to the virtual signal path in advance, ensuring that when the digital microphone stops generating signals, the output already has a stable virtual signal ready, thus preventing audio popping.
Solution Approach 2:
The patent introduces a mode selection element as an intermediary between the digital microphone and the output. This mode selection element can switch between different signal sources (digital microphone signal or virtual signal) based on control signals. During the transition, it mediates the switching process to ensure continuous stable output by selecting the appropriate signal source at each moment, preventing direct connection of unstable signals to the output.
2Speed
If the digital source is turned off immediately, then the switching process is fast, but unstable signals are transmitted to the back-end codec
Solution Approach 1:
The system performs preliminary switching to the virtual signal path before the digital microphone is completely turned off. The mode selection element responds to the turn-off signal by immediately switching the output to the virtual signal source, ensuring that the back-end codec receives a stable virtual signal throughout the entire transition period, even though the digital microphone is being turned off simultaneously.
3Object-generated harmful factors
If a virtual signal is used during switching, then audio popping is prevented, but additional circuit elements are required
Solution Approach 1:
The mode selection element serves as an intermediary that manages the switching between digital microphone signal and virtual signal. It receives control signals and automatically selects the appropriate input source, simplifying the overall control logic while enabling smooth transitions. The switching element acts as another intermediary that physically connects or disconnects different signal paths based on the mode selection element's output,从而实现 clean signal switching without audio popping.
Solution Approach 2:
The mode selection element and switching element are designed with multi-functionality, handling both the selection and physical switching functions. These elements can work with different signal sources and can be controlled through a unified interface, reducing the need for separate dedicated circuits for each function and thereby limiting the increase in overall device complexity.
Data Source
AI summary
A signal processing system and a signal processing method are provided. The signal processing method includes: in response to that a mode selection element receives a turn-off signal, outputting a first signal by the mode selection element; in response to that a switching element receives the first signal, switching from outputting a digital source signal to outputting a virtual signal by the switching element; in response to that a first delay element receives the first signal, outputting a first delay signal by the first delay element, where the first delay signal reaches a first voltage after a first delay time; and in response to that the first delay signal reaches the first voltage, stop outputting an output voltage by a power element.