| 摘要 |
<p>The invention relates to a filter circuit and a method for making a filter circuit comprising at least one gyrator core section (GCi) having four inverters mutually connected in a loop configuration between a pair of input terminals (i_1; i_2) and a pair of output terminals (o_1; o_2). At least one common mode feedback section (CMIi, CMOi) is provided between the pair of input terminals and/or the pair of output terminals. The common mode feedback section comprises two series connections respectively formed by an inverter and a short-sectioned inverter connected antiparallelly between the input terminals or the output terminals. The inverters may be constituted by a MOS, CMOS or BiCMOS or bipolar transistor. According to the invention, the channel region dimensions of the transistors of the gyrator core section and/or the common mode feedback section are selected such that the relationship g*C ≥ gm*cm is fulfilled, where g is the effective conductive loading of the gyrator core section terminals, C is the effective capacitive loading of the gyrator core section terminals, gm is the effective gyration constant of the gyrator core section, and cm is the effective transcapacitance of the gyrator core section.</p> |
