| 摘要 |
A low-pass filter has an element in series connected between input (14) and output (15) terminals, and an element in shunt with one terminal connected to the ground. The series element has a self-inductor (L1,L2) and the shunt element has a circuit with a resistor (R1,R2,R3) in series with a respective capacitor (C1',C2',C3'). Input (P1) and output (P2) pads are insulated from the grounded electrode (12) and connected respectively to the lines (S1,S2) by two wires (W). A cover (16) is connected electrically and mechanically to the grounded electrode (12) at the base of housing and covers the substrate (10) and the wires (W). The cover and the grounded electrode protect the filter circuit and also prevent the radiation of electromagnetic waves from the substrate surface. The element in series is placed at the input, and the element in shunt is placed at the output. The capacitors, the self-inductors, and the resistors each comprise a metallic strip. The filter has at least four stages. Independent claims are also included for (1) a receiver of optical signals with a photoelectric converter circuit designed to transform a received optical signal into an electrical signal; and (2) a low-pass filter with flat group delay characteristic. |
