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Electronics => Repair => Topic started by: wadmancpu on May 15, 2019, 01:26:17 am

Title: White silicone on plasma tv power supply board?
Post by: wadmancpu on May 15, 2019, 01:26:17 am

Anyone know what the white silicone like packing they put around fets and other components on power supply boards is? Purpose? Thanks.

Title: Re: White silicone on plasma tv power supply board?
Post by: Dacke on May 15, 2019, 03:27:57 am

If you mean around the legs of FETs,  it's just an extra measure to prevent dust buildup between the pins which can cause a short or arcing.  Usually more so around the PFC FETs as these operate at a higher voltage.  You also might commonly see isolation slots between the pins as well.  If you see the glue on other components like caps or inductors,  it's mostly for structural support.