Audio TDD

    a. The wiring should be run in parallel and protected by b, avoiding approaching large signal areas; c. The audio power supply should be clean; The audio filtering capacitor should be well grounded, and the bias power and ground of the mic should be well protected; The bias power supply and ground of the mic should be well protected; e. If the wiring is too long, the receiver AMP must be as close as possible to the CPU end. It can receive audio signals. If the wiring is too long, the receiver AMP must be as close as possible to the CPU end to amplify the sound signal before the audio signal is interfered with; f. The routing at both ends of the receiver should be as close as possible, with GND wrapped up and down. The routing at both ends of the receiver should be as close as possible, with GND wrapped up and down. g. The interference signal on the differential line can be expressed as a Common-mode interference part+differential mode interference part. The interference signal on the differential line can be expressed as a Common-mode interference part+capacitance between lines to remove differential mode interference, and the capacitance of each line to ground is to remove Common-mode interference. So special attention should be paid in this regard. Regarding the wiring between the grounding devices and the shells, the grounding must be fully connected. VBAT should not form a loop and should not interfere with the audio and other audio lines. The audio lines should be processed well and the edges should not have signals that are prone to vibration and high-speed digital signals that work simultaneously with audio. A filtering network should be reserved, Pay attention to the placement of audio devices, consider the similarities and differences between the PIFA antenna and the monopole antenna, and plan the audio well. Consider the similarities and differences between the PIFA antenna and the monopole antenna, especially the position of the components and the antenna, especially the MIC.