Title :
Digital frequency tuning technique based on current division for integrated active RC filters
Author :
Pun, Kong-Pang ; Choy, Chiu-Sing ; Chan, Cheong-Fat ; da Franca, J.E.
Author_Institution :
Dept. of Electron. Eng., Chinese Univ. of Hong Kong, Shatin, China
Abstract :
A novel digital frequency tuning technique is presented for integrated active RC filters. Instead of varying the values of the capacitors or resistors as in traditional approaches, the proposed technique achieves frequency tuning by dividing the currents that flow from resistors to virtual grounds. Current division is performed through a digitally programmable current division network added at each virtual ground. The technique features compact size, wide tuning range and high linearity. Transistor level simulation results are presented to demonstrate the technique.
Keywords :
RC circuits; active networks; circuit tuning; dividing circuits; programmable circuits; digital frequency tuning; digitally programmable current division network; integrated active RC filter; virtual ground;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:20030911