cupoftea
Advanced Member level 5
Hi,
Which are the modes of communication (USB etc), that are likely to comprise an earth connection?
I mean, supposing you have an offline SMPS on a PCB with an isolated secondary, and this secondary comprises circuitry that receives incoming comms lines from off the board…and suppose that those comms lines involve an earthed connection. -Then what that means is, that the secondary GND of the SMPS has been connected to earth ground…which in turn means that the offline SMPS will need sufficient common mode filtering to manage this….because as you know, offline isolated SMPS’s with earthed secondaries are far more noisy than those that don’t have earthing to their secondary.
Which are the modes of communication (USB etc), that are likely to comprise an earth connection?
I mean, supposing you have an offline SMPS on a PCB with an isolated secondary, and this secondary comprises circuitry that receives incoming comms lines from off the board…and suppose that those comms lines involve an earthed connection. -Then what that means is, that the secondary GND of the SMPS has been connected to earth ground…which in turn means that the offline SMPS will need sufficient common mode filtering to manage this….because as you know, offline isolated SMPS’s with earthed secondaries are far more noisy than those that don’t have earthing to their secondary.