USB charger from 2 wire DC wall adapter- connect USB shell to ground or leave floating?
If using a 5Vdc wall adapter as a USB charger for a phone would it be better from an EMI perspective to leave the USB shell floating at the connection to the wall adapter or connect it to the -ve side of the wall adapter output?
Can you please give an example of what would likely be a suitable high mu toroid (part #), keeping in mind I have very little space so the smaller the better.