The new CMOS 2V low-power if fully differential Rm-C bandpass amplifier for RF wireless receivers

Abstract

A new CMOS fully differential bandpass amplifier (BPA) based on the structure of transresistance (Rm) amplifier and capacitor is proposed and analyzed. In this design, the Fm amplifier is realized by a simple inverter with tunable shunt-shunt feedback MOS resistor and tunable negative resistance realized by the cross-coupled MOS transistors in parallel with a current source. The capacitor is in series with the input of Rm amplifier, which realize the biter function and block the de voltage. Under a 2-V supply voltage: the post-tuning capability of the gain can be as high as 90 dB whereas the tunable frequency range is between 41MHz and 178MHz. The power consumption is It mw and the dynamic range (DR) is 50 dB. The differential-mode gain is 20 dB and the common-mode gain is -25 dB so that the CMRR is 45 dB. Simple structure: good frequency response, and low power dissipation make the proposed bandpass amplifier quite feasible in the applications of IF stage for RF receivers.