Markus Grözing
Institute of Electrical and Optical Communication Engineering, University of Stuttgart
Daniel Moser
Institute of Electrical and Optical Communication Engineering, University of Stuttgart
Manfred Berroth
Institute of Electrical and Optical Communication Engineering, University of Stuttgart
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Published in: GigaHertz 2003. Proceedings from the Seventh Symposium
Linköping Electronic Conference Proceedings 8:27, p.
Published: 2003-11-06
ISBN:
ISSN: 1650-3686 (print), 1650-3740 (online)
A tunable differential active inductor and a switched bandpass amplifier in CMOS technology are presented. The active inductor is implemented in a 0;25 µm CMOS technology at a supply voltage of 2;5 V. The measured lower end of the inductance tuning range is 3;2 nH with estimated resonant frequency of 5;6 GHz and a current consumption of 13 mA. The inductance value can be tuned up to 23 nH with a measured resonant frequency of 1;9 GHz and a current consumption of 1;9 mA. The switched differential bandpass amplifier is implemented in a 0;18 µm CMOS technology at a supply voltage of 1;8 V. By activating the first or the second active inductor; the measured bandpass frequency can be switched between 100 MHz and 770 MHz. A modified switching concept of the active inductors can provide an amplifier with a bandpass frequency that can be switched between 125 MHz and 875 MHz in 125 MHz steps. Simulations indicate that the maximum gain is 16 dB for all 7 operation modes of the circuit.
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