I have a question about pulse transformer ,regarding to isolation, EMI reduction and heating.
- My PCB has 6 layers (4 signal and 2 power planes) and I am using pulse transformer to isolate and convert 3.3 from/to 5V. Maximal output current is 200mA.
- Switching frequency for this transformer is 600kHz.
- Is it better to use ceramic or tantalum or electrolytic capacitor at output?
I am wondering, should I keep area below transformer without copper ( all layers and planes) or should I place GND or isolated GND polygons, maybe on top layer?
My first thought was to remove copper on every layer and plane, below, but then make some fills (outward) around isolated GND pin and connect it with couple of vias to internal plane.
For capacitors I placed ceramic at input because of lower ESR and tantalum at output because better voltage stability.
What are your suggestions?