MOSFET heatsink conected to the ground through a cap

Discussion in 'General Electronics Chat' started by techieguy, Oct 28, 2013.

  1. techieguy

    Thread Starter New Member

    Oct 2, 2013
    Hello guys,

    I'm just learning a lot with these SMPS. There is a MOSFET (Q1) attached to a heatsink (isolated) and this heatsink has a pin which is inserted into the PCB, there is a capacitor in series with the heatsink (C37) which is connected to the ground (see picture attached). Anybody could help clarify what is the intent to connect the heatsink to the ground via a cap? Is is for better EMC compliance? Please note the Q1 is switching the main transformer.

    Thank you very much.