Digital auto-tuning system for analog filters

Abstract

In this paper, a new self-tuning digital technique is reported for analog filters over VHF (very high frequency) applications, based on phase detector. By using a 0.35 mum mixed signal CMOS process, changes in frequency response of a 3rd-order low pass filter can be tuned with a 3% error over the designed value. This technique confirms the feasibility of the proposed scheme in analog filter applications. The system consumes less area, power and tuning time than other proposed schemes. Simulation results show the building viability in a 10 MHz low pass filter.