IC EMI filter with ESD protection incorporating LC resonance tanks for rejection enhancement

摘要

An integrated circuit (IC) electromagnetic interference (EMI) filter with electrostatic discharge (ESD) protection incorporating inductor-capacitor (LC) resonance tanks is disclosed. The filter comprises at least one circuit composed of a diode and an inductor connected in series, wherein the diode induces a parasitic capacitance and the circuit is grounded. When a number of the circuit is two, a passive element is coupled between the two inductors and cooperates with them to induce two parasitic capacitances connected with the circuits. When a number of the circuit is one, two diodes respectively connect with the inductor through two passive elements. Each diode can induce a parasitic capacitance. The two passive elements and the inductor can induce a parasitic capacitance connected with the circuit.

主权项

1. An integrated circuit (IC) electromagnetic interference (EMI) filter with electrostatic discharge (ESD) protection incorporating inductor-capacitor (LC) resonance tanks, said IC EMI filter comprising:
a first diode with a first anode thereof coupled to a ground, wherein said first diode comprises a first parasitic capacitance between a first cathode of said first diode and said first anode; a first inductor having a first series resistance, and being coupled to said first cathode; a second diode with a second anode thereof coupled to said ground, wherein said second diode comprises a second parasitic capacitance between a second cathode of said second diode and said second anode; a second inductor having a second series resistance, and being coupled to said second cathode; and a first passive element coupled between said first and second inductors, wherein a first node between said first passive element and said first inductor is coupled to a first port, and a second node between said first passive element and said second inductor is coupled to a second port.