A Wide Dynamic Range Variable Gain Amplifier with Enhanced IP1 dB and Temperature Compensation

摘要

This paper presents the design consideration of a four-stage variable gain amplifier (VGA) with a wide dynamic range for receivers. The VGA uses parallel amplifiers for the first and second amplifiers in order to improve the input third-order intercept point (IIP3) in the low gain region. To investigate the behavior of the VGA, the gain and linearity analyses are newly derived for the parallel amplifiers, and are compared with the measured results. In addition, the principle of the temperature compensation is described. The gain control range of 110 dB, the IP1 dB of -11 dBm, and noise figure (NF) of 5.1 dB were measured using a 0.5 μm 26 GHz f_T BiCMOS process.