| 摘要 |
The invention relates to the measurement technology and radioelectronics and can be used for high-accuracy reproduction of floating impedances represented in Cartesian coordinates.The impedance converter comprises two cascades, each of which consists of a terminal (1, 2), an operational amplifier (3, 4), having its inverting input connected to the corresponding terminal (1, 2), and a resistor (5, 6), having one contact connected to the corresponding terminal (1, 2) and the other one - to the output of the operational amplifier (3, 4). The converter also contains the third resistor (7), a differential amplifier (8) with two inverting (9, 11) and two noninverting (10, 12) inputs, a phase shifter (15), a programmable amplifier (14), having its input connected to the output of the differential amplifier (8), and its output - to the input of the phase shifter (15). The converter also comprises an inverting amplifier (17) with unit amplification coefficient, having its input connected together with one noninverting input (10) of the differential amplifier (8) and one contact of the third resistor (7) to the noninverting input of the operational amplifier (3) of the first cascade and the output together with one inverting input (11) of the differential amplifier (8) and the other contact of the third resistor (7) - to the noninverting input of the operational amplifier (4) of the second cascade. The output of the operational amplifier (3) of the first cascade is connected to the other inverting input (9) of the differential amplifier (8), the other noninverting input (12) of which is connected to the output of the operational amplifier (4) of the second cascade. The impedance converter additionally comprises a second programmable amplifier (13), having its input connected to the output of the differential amplifier (8), a summing amplifier (16), having one input connected to the output of the phase shifter (15), the other input - to the output of the second programmable amplifier (13), and the output - to the input of the inverting amplifier (17).
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