Program possible notched width and possesses depth the notch filter

摘要

PURPOSE: To obtain a notch filter circuit which is programmable with respect to its notch width and depth. ;CONSTITUTION: A first switching capacitor resistor 37 is connected between the inputs of a filter circuit and a first amplifier and a second switching capacitor resistor 46 is connected between the output of the first amplifier and the input of a second amplifier, with the output of the second amplifier being connected to the output of the filter circuit. A third switching capacitor resistor 48 is connected between the output of the filter circuit and the input of the first amplifier and first and second programmable capacitor arrays 52 and 56 are respectively connected in parallel with the resistor 48 and, at the same time, in parallel with the resistor 37. Only the change of the capacitance of the second capacitor array 56 causes the corresponding change in the notch depth of a notch filter and only the change of the capacitance of the first capacitor array 52 causes the corresponding change in the notch width of the filter.;COPYRIGHT: (C)1995,JPO