Title :
An active tuning and impedance matching element
Author :
Lapinoja, M. ; Rahkonen, T.
Author_Institution :
Dept. of Electr. Eng., Oulu Univ., Finland
Abstract :
An integrated circuit that operates as a voltage controlled admittance with a constant real part and variable imaginary part is presented. It consists of two differential pairs, the inputs of which are phase shifted with respect to each other and their transconductance ratio can be varied. The circuit can be used as a combination of an active varactor and amplifier in integrated LC type voltage controlled oscillators, or as a tunable impedance matching element in RF inputs or outputs to compensate adaptively for the impedance mismatch due to temperature drift or large signal effects, for example
Keywords :
BiCMOS analogue integrated circuits; active networks; circuit tuning; compensation; electric admittance; impedance matching; voltage-controlled oscillators; 0 to 500 MHz; 1.2 micron; RF inputs; RF outputs; active tuning element; active varactor; adaptive impedance mismatch compensation; differential pairs; integrated LC type VCOs; large signal effects; temperature drift; tunable impedance matching element; variable transconductance ratio; voltage controlled admittance; voltage controlled oscillators; Admittance; Circuit optimization; Impedance matching; Radiofrequency amplifiers; Transconductance; Tunable circuits and devices; Tuning; Varactors; Voltage control; Voltage-controlled oscillators;
Conference_Titel :
Circuits and Systems, 1998. ISCAS '98. Proceedings of the 1998 IEEE International Symposium on
Conference_Location :
Monterey, CA
Print_ISBN :
0-7803-4455-3
DOI :
10.1109/ISCAS.1998.704570
