1.0SprintpcbGrouphttps://www.sprintpcbgroup.com/jaVoIP Gateway PCB Nearly Ruined by Ringing Noiserich600338<blockquote class="wp-embedded-content" data-secret="bdiWm2mp9a"><a href="https://www.sprintpcbgroup.com/ja/blogs/voip-gateway-pcb-ringing-noise-slic/">VoIP Gateway PCB Nearly Ruined by Ringing Noise</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.sprintpcbgroup.com/ja/blogs/voip-gateway-pcb-ringing-noise-slic/embed/#?secret=bdiWm2mp9a" width="600" height="338" title="“VoIP Gateway PCB Nearly Ruined by Ringing Noise” — SprintpcbGroup" data-secret="bdiWm2mp9a" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script>
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</script>https://www.sprintpcbgroup.com/wp-content/uploads/2026/10/voip-gateway-pcb-products.webp600400At power-up, the ringing current knocked out the microphone channel, and crackling noise infected the whole analog front end through the feedback loop while the digital side ran clean. This is the real failure scene when high-voltage ringing and a low-noise audio chain share one VoIP Gateway PCB. From laminate loss tangent to inner-layer copper heat dissipation and HDI microvia reliability in high-voltage areas, every ignored parameter takes revenge in volume production.