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Please read Cautions and warnings and

Important notes at the end of this document.

EMI suppression Film capacitors (MKP)

B32032 ... B32036

Y2 / 350 V AC

Application note

A Y capacitor to be connected between AC lines and the Frame Ground (FG) has an effect of emit-

ting common mode current to the FG.Leak current corresponding in frequency and voltage to the

AC power supply flows in the Y capacitor.

As the capacity of a Y capacitor grows, leak current also increases. This can cause electric shock.

Therefore, UL and other safety standards restrict the capacity so that the amount of leak current

does not exceed a certain level. Usually, two Y capacitors are used, as shown in figure below. As

AC lines are connected with capacitors; they are effective in reducing differential mode noises. In

particular, they are effective for high frequency ranges of 8 to 10 MHz.

Example of EMI suppression, typical application: