I'm building a rack-mounted audio switcher and need some advice on grounding. The power supply will be on a dedicated PCB, providing 5V for the microcontroller, 12V for relays and LEDs, and ±15V for the audio op-amps.
Would it be best to keep the power ground and audio ground separate, connecting them with a 10nF capacitor? Or should I connect them directly without the capacitor? Another option would be to tie the power ground to the chassis, with the connection to the audio ground controlled via a ground lift switch.
Would it be best to keep the power ground and audio ground separate, connecting them with a 10nF capacitor? Or should I connect them directly without the capacitor? Another option would be to tie the power ground to the chassis, with the connection to the audio ground controlled via a ground lift switch.
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Somewhere in one of your components or pcbs, they are probably already connected together.
But only connect the IEC safety ground directly to the chassis.
But only connect the IEC safety ground directly to the chassis.
attach the 'ground lift' circuit near the audio input connectors.
lose the ground coupling capacitor.
lose the ground coupling capacitor.
Hi, thanks for your response. After further research, I believe the best approach is to connect the power and audio ground together while carefully managing trace and wire routing.
Yes, DC supply common and audio circuit common together, then to the metal chassis near the input connectors.