Low Power, Low Voltage 95.1-dB Linear Variable Gain Amplifier with Diode Connected Load

A less gain error CMOS variable gain amplifier (VGA) with addition of diode connected load is presented. No additional circuit for gain control is required in the proposed design used in a Automatic gain control (AGC). A high linearity performance and a wide gain control voltage from 0.68 to 1V are achieved. Proposed VGA is fabricated in a 65nm CMOS technology and shows a gain range 104.64dB (-64.54dB to 40.10dB) and linear range 95.1dB (at frequency 67.78 KHz to 58.53MHz) with a linearity error 0.077 dB. The gain bandwidth is over 58.53 MHz at all gain settings. The whole circuit, occupying less area with 0.6uA current consumption and 0.6uW power consumption at 1V supply.