AF120 Datasheet | National Semiconductor

~National ~ Semiconductor Active Filters AF120 Generalized Impedance Converter, GIC General Description The AF120 contains a pair: of operational amplifiers and four precision thin film resistors connected as shown below. A gyrator may be formed by adding one external capacitor; or a frequency dependent negative resistance FDN R may be formed by adding two external capacitors. In the gyrator mode, ZIN a: jWC, which is equivalent to a grounded inductor. In the FDNR mode, ZIN a: - 1/ w 2 C1C2. The AF120 may also be used in pairs to form ungrounded inductors or inductor networks. Thus, with appropriate transformations, the G IC makes possible an active realization of any low-frequency...