Patent ID: 7623001

Claim:
An electromagnetic interference eliminating apparatus, having an input terminal and an output terminal, comprising: a multi-stage filter connected with the input terminal for receiving an input signal and providing an eliminating band to eliminate noise in the input signal, wherein the multi-stage filter comprises: a first resistor having two terminals, wherein a first of the two terminals of the first resistor is connected with the input terminal; a Y-shaped inductor circuit having three terminals, wherein a first of the three terminals of the Y-shaped inductor circuit is connected with a second of the two terminals of the first resistor; a Y-shaped capacitor circuit having three terminals, wherein the three terminals of the Y-shaped capacitor circuit are connected with the three terminals of the Y-shaped inductor circuit in parallel; and an active filter connected with the multi-stage filter and the output terminal for buffering the input signal and exactly outputting an output signal to the output terminal.