An 84 dB-gain-range and 1 GHz-bandwidth variable gain amplifier using gain flattening capacitors for multi-gigabit radio

Abstract

A 1 GHz wide-bandwidth digitally-controlled variable gain amplifier (VGA) with 84 dB wide gain range is presented for 60 GHz short range wireless systems. The VGA employs digitally-controlled resistors and gain flattening capacitors (GFCs) which improve in-band gain flatness. The VGA is fabricated in 90 nm CMOS. The measured result shows 84.3 dB gain tuning range from -25.3 dB to 59 dB with a 3 dB bandwidth of 1.0 GHz.