Digitally controlled wideband CMOS variable gain amplifier

A variable gain amplifier is designed for wideband system. The VGA is implemented in a 0.18 /spl mu/m CMOS process. The gain of the VGA is controlled digitally in dB using proposed a R ladder with switch and decoder. It operates at an IF frequency of 250 MHz and dynamic range is 27 dB.

[1]  Cheon-Soo Kim,et al.  A 1 GHz-band low distortion up-converter with a linear in dB control VGA for digital TV tuner , 2001, 2001 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium (IEEE Cat. No.01CH37173).

[2]  Sherif H. K. Embabi,et al.  A 60-dB 246-MHz CMOS variable gain amplifier for subsampling GSM receivers , 2003, IEEE Trans. Very Large Scale Integr. Syst..