I was told that one should reserve a distance of about 6.5 cm from the supply source to the output pins of the transformer. Encapsulated transfromers come built the way they do and the only reasonable way that i think it could be done would be to limit the charge on the primary pins using a ceramic capacitor of equal reactance to the resistance in the primary coil. This way i can provide the distance i need. Should i do this?
Thanks in advance.
If you are looking for the creepage/clearance distance (to keep the primary voltage from arcing to the secondary side), it’s a lot smaller than that. For my last design, I kept a 4mm spacing for 347V. See www.creepage.com for a calculator.
/mike
Thanks a lot. The thing is that even tho i put the bypass capacitors there’s still low noise. It was meant for an LM317 Regulator. Should I “snake-shape” the via between the the ripple capacitor and the filter capacitor. I made a new model wich printed today the distance is about 5 cm from the ripple to the input filter cap. I’m burning it tomorow. Hope it goes well.
tx n1ist