The simplest differential mode filter involves the placement of a single winding inductor in the line path and a capacitor between line and neutral. When high-frequency differential noise tries to circulate through the system, it comes up against the high impedance of the differential mode inductor and therefore takes the low impedance path through the capacitor. The differential mode choke effectively blocks the high frequency noise from moving through the system. It should be noted that because the differential mode inductor is in the line path it sees the full line current and therefore must be able to handle the peak power supply currents without saturating.