Digitally programmable current follower and its applications

In this paper, a CMOS implementation of the digitally programmable current follower (DP-CF) is presented. To achieve very low-input resistance, it is realized using a modification of a low-input resistance stage as an input stage. To achieve the precise digital control of the current gain, the current division technique is used. The proposed DP-CF is operated under ±1.5V voltage supplies, and designed with 0.5-μmμm CMOS SCN05H process. Applications of the proposed DP-CF in realizing digitally programmable current-mode filter and rectifier are given. SPICE simulation results of the proposed circuit and its applications are also included.