A High Dynamic Range CMOS Variable Gain Amplifier for Mobile DTV Tuner Academic Article uri icon

abstract

  • A high dynamic range RF variable gain amplifier (RFVGA) suitable for mobile digital television (DTV) tuners is presented. Variable gain is achieved using a capacitive attenuator and current-steering transconductance (Gm) stages, which provide high linearity with relatively low power consumption. A novel broadband input impedance matching scheme based on resistive shunt-feedback is proposed. This scheme allows the RFVGA to achieve a low noise figure. A gain control technique suitable for CMOS current-steering variable gain amplifiers is described; it features l dB per step resolution, independent of process and temperature variations. The chip is fabricated in six-metal 0.18 μm CMOS technology and consumes 12.2 mA current from 1.8 V supply. The RFVGA achieves 16 dB maximum gain, 33 dB gain control range, a 4.3 dB noise figure, and an IIP3 higher than 25 dBm. © 2007 IEEE.

altmetric score

  • 6

author list (cited authors)

  • Xiao, J., Mehr, I., & Silva-Martinez, J.

citation count

  • 76

publication date

  • February 2007